| |
Use the commands in this chapter to configure and monitor source-route bridging (SRB) networks. For SRB configuration information and examples, refer to the "Configuring Source-Route Bridging" chapter in the Bridging and IBM Networking Configuration Guide.
Use the access-expression interface configuration command to define an access expression. Use the no form of this command to remove the access expression from the given interface. You use this command in conjunction with the access-list interface configuration command.
Syntax Description
Defaults
No access expression is defined.
Command Modes
Command History
Usage Guidelines
An access expression consists of a list of terms, separated by Boolean operators, and optionally grouped in parentheses.
An access expression term specifies a type of access list, followed by its name or number. The result of the term is either true or false, depending on whether the access list specified in the term permits or denies the frame. Table 12 describes the terms that can be used.
Access expression terms are separated by Boolean operators as listed in Table 13.
Terms can be grouped in parenthetical expressions. Any of the terms and operators can be placed in parentheses, similar to what is done in arithmetic expressions, to affect order of evaluation.
An "access-expression" type filter cannot exist with a "source-bridge" type filter on the same interface. The two types of filters are mutually exclusive.
 |
Note The incorrect use of parentheses can drastically affect the result of an operation, because the expression is read left to right. |
Related Commands
| Command | Description |
|---|---|
|
Configures the access list mechanism for filtering frames by protocol type or vendor code. |
Use the access-list global configuration command to configure the access list mechanism for filtering frames by protocol type or vendor code. Use the no form of this command to remove the single specified entry from the access list.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
For source address filtering, the mask always should have the high-order bit set. This is because the IEEE 802 standard uses this bit to indicate whether a RIF is present, not as part of the source address.
For a list of type codes, refer to the "Ethernet Type Codes" appendix of this manual.
Examples
In the following example, the access list permits only Novell frames (LSAP 0xE0E0) and filters out all other frame types. This set of access lists would be applied to an interface via the source-bridge input-lsap list or source-bridge input-lsap list commands (described later in this chapter).
Combine the DSAP/LSAP fields into one
number to do LSAP filtering; for example,
0xE0E0—not 0xE0. Note that the
deny condition specified in the preceding example is not required; access lists
have an implicit deny as the last statement. Adding this statement can serve as
a useful reminder, however.
The following access list filters out
only SNAP type codes assigned to DEC (0x6000 to 0x6007) and lets all other types
pass. This set of access lists would be applied to an interface using the
source-bridge
input-type-list or source-bridge
output-type-list commands (described later in this chapter).
|
Note Use the last item of an access list to specify a default action; for example, to permit everything else or to deny everything else. If nothing else in the access list matches, the default action is to deny access; that is, filter out all other type codes. |
Type code access lists will negatively affect system performance by greater than 30 percent. Therefore, it is recommended that you keep the lists as short as possible and use wildcard bit masks whenever possible.
Related Commands
Use the bridge protocol ibm global configuration command to create a bridge group that runs the automatic spanning-tree function. Use the no form of this command to cancel the previous assignment.
Syntax Description
Defaults
Command Modes
Command History
Examples
The following example specifies bridge 1 to use the automatic spanning-tree function:
Related Commands
| Command | Description |
|---|---|
|
Displays the current source bridge configuration and miscellaneous statistics. | |
|
Enables the automatic spanning-tree function for a specified group of bridged interfaces. | |
Use the clear netbios-cache privileged EXEC command to clear the entries of all dynamically learned NetBIOS names. This command will not remove statically defined name cache entries.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Usage Guidelines
The Cisco IOS software automatically learns NetBIOS names. This command clears those entries.
Examples
The following example clears all dynamically learned NetBIOS names:
Related Commands
| Command | Description |
|---|---|
|
Enables NetBIOS name caching and sets the time that entries can remain in the NetBIOS name cache. | |
Use the clear rif-cache privileged EXEC command to clear the entire RIF cache.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Usage Guidelines
Some entries in the RIF cache are dynamically added and others are static.
Examples
The following example clears the entire RIF cache:
Related Commands
Use the clear source-bridge privileged EXEC command to clear the source-bridge statistical counters.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following example clears the source-bridge statistical counters:
Related Commands
| Command | Description |
|---|---|
|
Removes any learned entries from the forwarding database and clears the transmit and receive counts for any statically or system-configured entries. |
Use the clear sse privileged EXEC command to reinitialize the Silicon Switch Processor (SSP) on the Cisco 7000 series routers with RSP7000.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The silicon switching engine (SSE) is on the SSP board in the Cisco 7000 series routers with RSP7000.
Examples
The following example reinitializes the SSP:
Use the ethernet-transit-oui interface configuration command to choose the Organizational Unique Identifier (OUI) code to be used in the encapsulation of Ethernet Type II frames across Token Ring backbone networks. Various versions of this OUI code are used by Ethernet/Token Ring translational bridges. Use the no form of this command to return the default OUI code.
Syntax Description
Defaults
The default OUI form is 90-compatible.
Command Modes
Command History
Usage Guidelines
Before using this command, you must have completely configured your router using multiport source-bridging and transparent bridging.
The standard keyword is used when you are forced to interoperate with other vendor equipment, such as the IBM 8209, in providing Ethernet and Token Ring mixed media bridged connectivity.
The actual OUI codes that are used, when they are used, and how they compare to Software Release 9.0-equivalent commands are shown in Table 14.
Specify the 90-compatible keyword when talking to our routers. This keyword provides the most flexibility. When 90-compatible is specified or the default is used, Token Ring frames with an OUI of 0x0000F8 are translated into Ethernet Type II frames while Token Ring frames with the OUI of 0x000000 are translated into SNAP-encapsulated frames. Specify the standard keyword when talking to IBM 8209 bridges and other vendor equipment. This OUI does not provide for as much flexibility as the other two choices. The cisco OUI is provided for compatibility with future equipment.
Do not use the standard keyword unless you are forced to interoperate with other vendor equipment, such as the IBM 8209, in providing Ethernet and Token Ring mixed media bridged connectivity. Only use the standard keyword when you are transferring data between IBM 8209 Ethernet/Token Ring bridges and routers running the SR/TLB software (to create a Token Ring backbone to connect Ethernets).
Use of the standard keyword causes the OUI code in Token Ring frames to always be 0x000000. In the context of the standard keyword, an OUI of 0x000000 identifies the frame as an Ethernet Type II frame. (Compare with 90-compatible, where 0x000000 OUI means SNAP-encapsulated frames.)
If you use the 90-compatible keyword, the router, acting as an SR/TLB, can distinguish immediately on Token Ring interfaces between frames that started on an Ethernet Type II frame and those that started on an Ethernet as a SNAP-encapsulated frame. The distinction is possible because the router uses the 0x0000F8 OUI when converting Ethernet Type II frames into Token Ring SNAP frames, and leaves the OUI as 0x000000 for Ethernet SNAP frames going to a Token Ring. This distinction in OUIs leads to efficiencies in the design and execution of the SR/TLB product; no tables need to be kept to know which Ethernet hosts use SNAP encapsulation and which hosts use Ethernet Type II.
The IBM 8209 bridges, however, by using the 0x000000 OUI for all the frames entering the Token Ring, must take extra measures to perform the translation. For every station on each Ethernet, the 8209 bridges attempt to remember the frame format used by each station, and assume that once a station sends out a frame using Ethernet Type II or 802.3, it will always continue to do so. It must do this because in using 0x000000 as an OUI, there is no way to distinguish between SNAP and Type II frame types. Because the SR/TLB router does not need to keep this database, when 8209 compatibility is enabled with the standard keyword, the SR/TLB chooses to translate all Token Ring SNAP frames into Ethernet Type II frames as described earlier in this discussion. Because every nonroutable protocol on Ethernet uses either non SNAP 802.3 (which traverses fully across a mixed IBM 8209/ router Token Ring backbone) or Ethernet Type II, this results in correct interconnectivity for virtually all applications.
Do not use the standard OUI if you want SR/TLB to output Ethernet SNAP frames. Using either the 90-compatible or cisco OUI does not present such a restriction, because SNAP frames and Ethernet Type II-encapsulated frames have different OUI codes on Token Ring networks.
Examples
The following example specifies standard OUI form:
Related Commands
Use the lnm alternate interface configuration command to specify the threshold reporting link number. In order for a LAN Reporting Manager (LRM) to change parameters, it must be attached to the reporting link with the lowest reporting link number, and that reporting link number must be lower than this threshold reporting link number. Use the no form of this command to restore the default of 0.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
LAN Network Manager (LNM) employs the concepts of reporting links and reporting link numbers. A reporting link is simply a connection (or potential connection) between an LRM and a bridge. A reporting link number is a unique number used to identify a reporting link. An IBM bridge allows four simultaneous reporting links numbered 0 to 3. Only the LRM attached to the lowest number connection is allowed to change any parameters, and then only when that connection number falls below a certain configurable number. In the default configuration, the LRM connected through link 0 is the only LRM allowed to change parameters.
|
Note Setting the threshold reporting link number on one interface in a source-route bridge will cause it to appear on the other interface of the bridge, because the command applies to the bridge itself and not to either of the interfaces. |
Examples
The following example permits LRMs connected through links 0 and 1 to change parameters:
The following example permits all LRMs to change parameters in the Cisco IOS software:
Related Commands
| Command | Description |
|---|---|
Use the lnm crs interface configuration command to monitor the current logical configuration of a Token Ring. Use the no form of this command to disable this function.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The Configuration Report Server service keeps track of the current logical configuration of a Token Ring and reports any changes to LNM. It also reports on various other activities such as the change of the Active Monitor on a Token Ring.
For more information about the Active Monitor, refer to the IBM Token Ring Architecture Reference Manual or the IEEE 802.5 specification.
Examples
The following example disables monitoring of the current logical configuration of a Token Ring:
Related Commands
| Command | Description |
|---|---|
|
Ensures that all stations on a ring are using a consistent set of reporting parameters. |
Use the lnm disabled global configuration command to disable LNM functionality. Use the no form of this command to restore LNM functionality.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
Under some circumstances, you can disable all LNM server functions on the router without having to determine whether to disable a specific server, such as the ring parameter server or the ring error monitor on a given interface.
This command can be used to terminate all LNM server input and reporting links. In normal circumstances, this command should not be necessary because it is a superset of the functions normally performed on individual interfaces by the no lnm rem and no lnm rps commands.
Examples
The following example disables LNM functionality:
Related Commands
Use the lnm express-buffer interface configuration command to enable the LNM RPS express buffer function. Use the no form of this command to disable the function.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The RPS express buffer function allows the router to set the express buffer bit to ensure priority service for frames required for ring station initiation. When this function is enabled, the router sets the express buffer bit in its initialize ring station response. This allows Token Ring devices to insert into the ring during bursty conditions.
Examples
The following example enables the LNM RPS express buffer function:
Use the lnm loss-threshold interface configuration command to set the threshold at which the Cisco IOS software sends a message informing all attached LNMs that it is dropping frames. Use the no form of this command to return to the default value.
Syntax Description
|
A single number expressing the percentage loss rate in hundredths of a percent. The valid range is 0 to 9999. |
Defaults
Command Modes
Command History
Usage Guidelines
The software sends a message to all attached LNMs whenever it begins to drop frames. The point at which this report is generated (threshold) is a percentage of the number of frames dropped compared with the number of frames forwarded.
When setting this value, remember that 9999 would mean 100 percent of your frames could be dropped before the message is sent. A value of 1000 would mean 10 percent of the frames could be dropped before sending the message. A value of 100 would mean 1 percent of the frames could be dropped before the message is sent.
Examples
In the following example, the loss threshold is set to 0.02 percent:
Use the lnm password interface configuration command to set the password for the reporting link. Use the no form of this command to return the password to its default value of 00000000.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
LNM employs the concepts of reporting links and reporting link numbers. A reporting link is simply a connection (or potential connection) between a LAN Reporting Manager (LRM) and a bridge. A reporting link number is a unique number used to identify a reporting link. An IBM bridge allows four simultaneous reporting links numbered 0 to 3. Only the LRM attached to the lowest number connection is allowed to change any parameters, and then only when that connection number falls below a certain configurable number. In the default configuration, the LRM connected through link 0 is the only LRM allowed to change parameters.
Each reporting link has its own password. Passwords are used not only to prevent unauthorized access from an LRM to a bridge, but to control access to the different reporting links. This is important because of the different abilities associated with the various reporting links.
Characters allowable in the string are the following:
Passwords are displayed only through use of the privileged EXEC show running-config command.
|
Note There are two parameters in an IBM bridge that have no corresponding parameter in the Cisco IOS software. This means that any attempt to modify these parameters from LNM will fail and display an error message. The LNM names of these two parameters are route active status and single route broadcast mode. |
Examples
In the following example, the password Zephyr@ is assigned to reporting link 2:
Related Commands
Use the lnm pathtrace-disabled global configuration command to disable pathtrace reporting to LNM stations. Use the no form of this command to restore pathtrace reporting functionality.
Syntax Description
|
(Optional) Disable pathtrace reporting to the LNM and originating stations. | |
|
(Optional) Disable pathtrace reporting to originating stations only. |
Defaults
Command Modes
Command History
Usage Guidelines
Under some circumstances, such as when new hardware has been introduced into the network and is causing problems, the automatic report path trace function can be disabled. The new hardware may be setting bit-fields B1 or B2 (or both) of the routing control field in the routing information field embedded in a source-route bridged frame. This condition may cause the network to be flooded by report path trace frames if the condition is persistent. The lnm pathtrace-disabled command, along with its options, allows you to alleviate network congestion that may be occurring by disabling all or part of the automatic report path trace function within LNM.
Examples
The following example disables all pathtrace reporting:
Related Commands
| Command | Description |
|---|---|
|
Displays all currently configured bridges and all parameters that are related to the bridge as a whole, not to one of its interfaces. |
Use the lnm rem interface configuration command to monitor errors reported by any station on the ring. Use the no form of this command to disable this function.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The Ring Error Monitor (REM) service monitors errors reported by any station on the ring. It also monitors whether the ring is in a functional state or in a failure state.
Examples
The following example shows the use of the lnm rem command:
Related Commands
| Command | Description |
|---|---|
|
Ensures that all stations on a ring are using a consistent set of reporting parameters. |
Use the lnm rps interface configuration command to ensure that all stations on a ring are using a consistent set of reporting parameters. Use the no form of this command to disable this function.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The Ring Parameter Server (RPS) service ensures that all stations on a ring are using a consistent set of reporting parameters and are reporting to LNM when any new station joins a Token Ring.
Examples
The following example shows the use of the lnm rps command:
Related Commands
| Command | Description |
|---|---|
Use the lnm snmp-only global configuration command to prevent any LNM stations from modifying parameters in the Cisco IOS software. Use the no form of this command to allow modifications.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
Configuring a router for LNM support is very simple. It happens automatically as a part of configuring the router to act as a source-route bridge. There are several commands available to modify the behavior of the LNM support, but none of them are necessary for it to function.
Because there is now more than one way to remotely change parameters in the Cisco IOS software, this command was developed to prevent them from detrimentally interacting with each other.
This command does not affect the ability of LNM to monitor events, only to modify parameters in the Cisco IOS software.
Examples
The following command prevents any LNM stations from modifying parameters in the software:
Use the lnm softerr interface configuration command to set the time interval in which the Cisco IOS software will accumulate error messages before sending them. Use the no form of this command to return to the default value.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
All stations on a Token Ring notify the REM when they detect errors on the ring. To prevent an excessive number of messages, error reports are not sent immediately, but are accumulated for a short period of time and then reported. A station learns this value from a router (configured as a source-route bridge) when it first enters the ring.
Examples
The following example changes the error-reporting frequency to once every 5 seconds:
Related Commands
| Command | Description |
|---|---|
Use the mac-address interface configuration command to set the MAC layer address of the Cisco Token Ring.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
There is a known defect in earlier forms of this command when using the Texas Instruments Token Ring MAC firmware. This implementation is used by Proteon, Apollo, and IBM RTs. A host using a MAC address whose first two bytes are zeros (such as a Cisco router) will not properly communicate with hosts using that form of this command of TI firmware.
There are two solutions. The first involves installing a static RIF entry for every faulty node with which the router communicates. If there are many such nodes on the ring, this may not be practical. The second solution involves setting the MAC address of the Cisco Token Ring to a value that works around the problem.
This command forces the use of a different MAC address on the specified interface, thereby avoiding the Texas Instrument MAC firmware problem. It is up to the network administrator to ensure that no other host on the network is using that MAC address.
Examples
The following example sets the MAC layer address, where xx.xxxx is an appropriate second half of the MAC address to use:
Use the multiring interface configuration command to enable collection and use of RIF information. Use the no form of this command to disable the use of RIF information for the protocol specified.
Syntax Description
|
Specifies a protocol; see the keyword list under the "Usage Guidelines" section. | |
|
Enables the multiring for any routed frame not included in the previous list of supported protocols. |
Defaults
Command Modes
Command History
| Release | Modification |
|---|---|
Usage Guidelines
Level 3 routers that use protocol-specific information (for example, Novell IPX or XNS headers) rather than MAC information to route datagrams also must be able to collect and use RIF information to ensure that they can transmit datagrams across a source-route bridge. The software default is to not collect and use RIF information for routed protocols. This allows operation with software that does not understand or properly use RIF information.
The current software allows you to specify a protocol. This is specified by the argument protocol-keyword. The protocols supported and the keywords you can enter include the following:
The multiring command was extended in Software Release 8.3 to allow for per-protocol specification of the interface's ability to append RIFs to routed protocols. When it is enabled for a protocol, the router will source packets that include information used by source-route bridges. This allows a router with Token Ring interfaces, for the protocol or protocols specified, to connect to a source-bridged Token Ring network. If a protocol is not specified for multiring, the router can only route packets to nodes directly connected to its local Token Ring.
Examples
The following example enables IP and Novell IPX bridging on a Token Ring interface. RIFs will be generated for IP frames, but not for the Novell IPX frames.
Related Commands
Use the netbios access-list bytes global configuration command to define the offset and hexadecimal patterns with which to match byte offsets in NetBIOS packets. Use the no form of this command to remove an entire list or the entry specified with the pattern argument.
Syntax Description
Defaults
No offset or pattern is defined.
Command Modes
Command History
Usage Guidelines
For offset pattern matching, the byte pattern must be an even number of hexadecimal digits in length.
The byte pattern must be no more than 16 bytes (32 hexadecimal digits) in length.
As with all access lists, the NetBIOS access lists are scanned in order.
You can specify a wildcard character in the byte string indicating that the value of that byte does not matter in the comparison. This is done by specifying two asterisks (**) in place of digits for that byte. For example, the following command would match 0xabaacd, 0xab00cd, and so on:
Examples
The following example shows how to configure for offset pattern matching:
In the following example, the byte pattern would not be accepted because it must be an even number of hexadecimal digits:
In the following example, the byte pattern would not be permitted because the byte pattern is longer than 16 bytes in length:
The following example would match 0xabaacd, 0xab00cd, and so on:
The following example deletes the entire marketing NetBIOS access list named marketing:
The following example removes a single entry from the list:
In the following example, the first line serves to deny all packets with a byte pattern starting in offset 3 of 0xab. However, this denial would also include the pattern 0xabcd because the entry permitting the pattern 0xabcd comes after the first entry:
Related Commands
| Command | Description |
|---|---|
|
Defines a byte access list filter on incoming messages. The actual access filter byte offsets and patterns used are defined in one or more netbios-access-list bytes commands. | |
Use the netbios access-list host global configuration command to assign the name of the access list to a station or set of stations on the network. The NetBIOS station access list contains the station name to match, along with a permit or deny condition. Use the no form of this command to remove either an entire list or just a single entry from a list, depending upon the argument given for pattern.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
Table 15 explains the pattern-matching characters that can be used.
Examples
The following example specifies a full station name to match:
The following example specifies a prefix where the pattern matches any name beginning with the characters DEFG:
The following example permits any station name with the letter W as the first character and the letter Y as the third character in the name. The second and fourth character in the name can be any character. This example would allow stations named WXYZ and WAYB; however, stations named WY and WXY would not be allowed because the question mark (?) must match specific characters in the name:
The following example illustrates how to combine wildcard characters. In this example the marketing list denies any name beginning with AC that is not at least three characters in length (the question mark [?] would match any third character). The string ACBD and ACB would match, but the string AC would not:
In the following example, a single entry in the marketing NetBIOS access list is removed:
In the following example, the entire marketing NetBIOS access list is removed:
Related Commands
| Command | Description |
|---|---|
|
Defines a station access list filter on incoming messages. The access lists of station names are defined in netbios access-list host commands. | |
Use the netbios enable-name-cache interface configuration command to enable NetBIOS name caching. Use the no form of this command to disable the name-cache behavior.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
This command enables the NetBIOS name cache on the specified interface. By default the name cache is disabled for the interface. Proxy explorers must be enabled on any interface that is using the NetBIOS name cache.
Examples
The following example enables NetBIOS name caching for Token Ring interface 0:
Related Commands
Use the netbios input-access-filter bytes interface configuration command to define a byte access list filter on incoming messages. The actual access filter byte offsets and patterns used are defined in one or more netbios-access-list bytes commands. Use the no form of this command with the appropriate name to remove the entire access list.
Syntax Description
|
Name of a NetBIOS access filter previously defined with one or more of the netbios access-list bytes global configuration commands. |
Defaults
Command Modes
Command History
Usage Guidelines
The following example applies a previously defined filter named marketing to packets coming into tokenring 1:
Related Commands
Use the netbios input-access-filter host interface configuration command to define a station access list filter on incoming messages. The access lists of station names are defined in netbios access-list host commands. Use the no form of this command with the appropriate argument to remove the entire access list.
Syntax Description
|
Name of a NetBIOS access filter previously defined with one or more of the netbios access-list host global configuration commands. |
Defaults
Command Modes
Command History
Examples
The following example filters packets coming into tokenring1 using the NetBIOS access list named marketing:
Related Commands
Use the netbios name-cache global configuration command to define a static NetBIOS name cache entry, tying the server with the name netbios-name to the mac-address, and specifying that the server is accessible either locally via the interface-name specified, or remotely, via the ring-group group-number specified. Use the no form of this command to remove the entry.
Syntax Description
|
Name of the interface by which the server is accessible locally. | |
|
Number of the ring group by which the server is accessible remotely. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 to 4095. |
Defaults
Command Modes
Command History
Usage Guidelines
To specify an entry in the static name cache, first specify a Routing Information Field (RIF) that leads to the server's MAC address. The Cisco IOS software displays an error message if it cannot find a static RIF entry for the server when the NetBIOS name-cache entry is attempted or if the server's type conflicts with that given for the static RIF entry.
|
Note The names are case sensitive; therefore "Cc" is not the same as "cC". |
Examples
The following example indicates the syntax usage of this command if the NetBIOS server is accessed locally:
The following example indicates the syntax usage of this command if the NetBIOS server is accessed remotely:
Related Commands
| Command | Description |
|---|---|
Use the netbios name-cache name-len global configuration command to specify how many characters of the NetBIOS type name the name cache will validate.
Syntax Description
Defaults
Command Modes
Command History
Examples
The following example specifies that the name cache will validate 16 characters of the NetBIOS type name:
Related Commands
Use the netbios name-cache proxy-datagram global configuration command to enable the Cisco IOS software to act as a proxy and send NetBIOS datagram type frames.
Syntax Description
|
Time interval, in seconds, that the software forwards a route broadcast datagram type packet. The valid range is any number greater than 0. |
Defaults
There is no default time interval.
Command Modes
Command History
Examples
The following example specifies that the software will forward a NetBIOS datagram type frame in 20-second intervals:
Related Commands
Use the netbios name-cache query-timeout global configuration command to specify the "dead" time, in seconds, that starts when a host sends any ADD_NAME_QUERY, ADD_GROUP_NAME, or STATUS_QUERY frame. During this dead time, the Cisco IOS software drops any repeat, duplicate ADD_NAME_QUERY, ADD_GROUP_NAME, or STATUS_QUERY frame sent by the same host. This timeout is only effective at the time of the login negotiation process. Use the no form of this command to bring the time back to the default of 6 seconds.
Syntax Description
Defaults
Command Modes
Command History
Examples
The following example sets the timeout to 15 seconds:
Related Commands
Use the netbios name-cache recognized-timeout global configuration command to specify the "dead" time, in seconds, that starts when a host sends any FIND_NAME or NAME_RECOGNIZED frame. During this dead time, the Cisco IOS software drops any repeat, duplicate FIND_NAME or NAME_RECOGNIZED frame sent by the same host. This timeout is only effective at the time of the login negotiation process. Use the no form of this command to bring the time back to the default of 6 seconds.
Syntax Description
Defaults
Command Modes
Command History
Examples
The following example sets the timeout to 15 seconds:
Related Commands
Use the netbios name-cache timeout global configuration command to enable NetBIOS name caching and to set the time that entries can remain in the NetBIOS name cache. Use the no form of this command to bring the time back to the default of 15 minutes.
Syntax Description
|
Time, in minutes, that entries can remain in the NetBIOS name cache. Once the time expires, the entry will be deleted from the cache. Default is 15 minutes. |
Defaults
Command Modes
Command History
Usage Guidelines
This command allows you to establish NetBIOS name caching. NetBIOS name caching can be used only between routers that are running Software Release 9.1 or later. NetBIOS name-caching does not apply to static entries.
Examples
The following example sets the timeout to 10 minutes:
Related Commands
| Command | Description |
|---|---|
Use the netbios output-access-filter bytes interface configuration command to define a byte access list filter on outgoing messages. Use the no form of this command to remove the entire access list.
Syntax Description
|
Name of a NetBIOS access filter previously defined with one or more of the netbios access-list bytes global configuration commands. |
Defaults
Command Modes
Command History
Examples
The following example filters packets leaving tokenring 1 using the NetBIOS access list named engineering:
Related Commands
Use the netbios output-access-filter host interface configuration command to define a station access list filter on outgoing messages. Use the no form of this command to remove the entire access list.
Syntax Description
|
Name of a NetBIOS access filter previously defined with one or more of the netbios access-list host global configuration commands. |
Defaults
No access list filter is defined.
Command Modes
Command History
Examples
The following example filters packets leaving tokenring 1 using the NetBIOS access list named engineering:
Related Commands
Use the rif global configuration command to enter static source-route information into the Routing Information Field (RIF) cache. If a Token Ring host does not support the use of IEEE 802.2 TEST or XID datagrams as explorer packets, you may need to add static information to the RIF cache of the router. Use the no form of this command to remove an entry from the cache.
Syntax Description
|
12-digit hexadecimal string written as a dotted triplet; for example, 0010.0a00.20a6. | |
|
Series of 4-digit hexadecimal numbers separated by a period (.). This RIF string is inserted into the packets sent to the specified MAC address. | |
|
Interface name (for example, tokenring 0) that indicates the origin of the RIF. | |
|
Ring group number that indicates the origin of the RIF. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 to 4095. |
Defaults
No static source-route information is entered.
Command Modes
Command History
Usage Guidelines
You must specify either an interface name or a ring group number to indicate the origin of the RIF. You specify an interface name (for example, tokenring 0) with the interface-name argument, and you specify a ring group number with the ring-group ring argument. The ring group number must match the number you specified with the source-bridge ring-group command. Ring groups are explained in the "Configuring Source-Route Bridging" chapter of the Bridging and IBM Networking Configuration Guide.
Using the command rif mac-address without any other arguments puts an entry into the RIF cache indicating that packets for this MAC address should not have RIF information.
Do not configure a static RIF with any of the all rings type codes. Doing so causes traffic for the configured host to appear on more than one ring and leads to unnecessary congestion.
|
Note Input to the source-bridge interface configuration command is in decimal format. RIF displays and input are in hexadecimal format, and IBM source-route bridges use hexadecimal for input. It is essential that bridge and ring numbers are consistent for proper network operation. This means you must explicitly declare the numbers to be hexadecimal by preceding the number with 0x, or you must convert IBM hexadecimal numbers to a decimal equivalent when entering them. For example, IBM hexadecimal bridge number 10 would be entered as hexadecimal number 0x10 or decimal number 16 in the configuration commands. In the displays, these commands always will be in decimal. |
Examples
The following example configuration sets up a static RIF:
Related Commands
| Command | Description |
|---|---|
Use the rif timeout global configuration command to determine the number of minutes an inactive RIF entry is kept. RIF information is maintained in a cache whose entries are aged. Use the no form of this command to restore the default.
Syntax Description
|
Number of minutes an inactive RIF entry is kept. The value must be greater than 0. Default is 15 minutes. |
Defaults
Command Modes
Command History
Usage Guidelines
A RIF entry is cached based on the MAC address and the interface.
A RIF entry can be aged out even if there is active traffic, but the traffic is fast or autonomously switched.
A RIF entry is refreshed only if a RIF field of an incoming frame is identical to the RIF information of the RIF entry in the cache.
Until a RIF entry is removed from the cache, no new information is accepted for that RIF entry.
Examples
The following example changes the timeout period to 5 minutes:
Related Commands
| Command | Description |
|---|---|
|
Enables RIF validation for entries learned on an interface (Token Ring or FDDI). | |
Use the rif validate-age global configuration command to define the validation time when the Cisco IOS software is acting as a proxy for NetBIOS NAME_QUERY packet or for explorer frames.
Syntax Description
|
Interval, in seconds, at which a proxy is sent. The valid range is any number greater than 0. Default is 2 seconds. |
Defaults
Command Modes
Command History
Usage Guidelines
If the timer expires before the response is received, the RIF entry or the NetBIOS cache entry is marked as invalid and is flushed from the cache table when another explorer or NAME_QUERY packet is received.
Examples
The following example specifies the interval at which a proxy is sent to be 3 seconds:
Related Commands
Use the rif validate-enable global configuration command to enable RIF validation for entries learned on an interface (Token Ring or FDDI). Use the no form of this command to disable the specification.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
A RIF validation algorithm is used for the following cases:
A directed IEEE TEST command is sent to the destination MAC address. If a response received in the time specified by rif validate-age, the entry is refreshed and is considered valid. Otherwise, the entry is removed from the cache. To prevent sending too many TEST commands, any entry that has been refreshed in less than 70 seconds is considered valid.
Validation is triggered as follows:
|
Note If the RIF entry has been in the RIF cache for 6 hours, and has not been refreshed for the time specified in the rif timeout command, the entry is removed unconditionally from the cache. |
|
Note The rif validate-enable commands have no effect on remote entries learned over RSRB. |
Examples
The following example enables RIF validation:
Related Commands
Use the rif validate-enable-age global configuration command to enable RIF validation for stations on a source-route bridge network that do not respond to an IEEE TEST command. Use the no form of this command to disable the specification.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
You must first issue the rif validate-enable command.
When this command is enabled, a RIF entry is not removed from the cache even if it becomes invalid. If the entry is refreshed, it becomes valid again.
If a RIF field of an incoming frame and the RIF information of the invalid RIF entry are not identical, the old RIF information is replaced by the new information.
|
Note The rif validate-enable commands have no effect on remote entries learned over RSRB. |
Examples
The following example enables RIF validation:
Related Commands
| Command | Description |
|---|---|
|
Enables RIF validation for entries learned on an interface (Token Ring or FDDI). |
Use the rif validate-enable-route-cache global configuration command to enable synchronization of the RIF cache with the protocol route cache. Use the no form of this command to disable the specification.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
When a RIF entry is removed from the RIF cache, or the RIF information in the RIF entry is changed, the protocol route caches are synchronized with the RIF cache.
|
Note The rif validate-enable commands have no effect on remote entries learned over RSRB. |
Examples
The following example synchronizes the RIF cache with the protocol route cache:
Related Commands
| Command | Description |
|---|---|
|
Enables RIF validation for entries learned on an interface (Token Ring or FDDI). |
To display the defined input and output access list expressions, use the show access-expression EXEC command.
Syntax Description
Defaults
Displays all input and output access list expressions.
Command Modes
Command History
Examples
The following is sample output from the show access-expression command:
Please see the access-expression command for a description of the access expressions.
Use the show controllers token privileged EXEC command to display information about memory management, error counters, and the board itself. Depending on the board being used, the output can vary. This command also displays proprietary information. Thus, the information that show controllers token displays is of primary use to our technical personnel. Information that is useful to users can be obtained with the show interfaces tokenring command, described later.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following is sample output from the
show controllers token command of a CSC-IR or
CSC-2R
card:
Table 16, Part 1 describes the fields shown in the first line of sample output.
In the following line, state 3 indicates the state of the board. The rest of this output line displays memory mapping that is of primary use to our engineers.
The following line also appears in show interface token output as the address and burned in address (bia), respectively:
The following line displays buffer management pointers that change by board:
The following line indicates the ring status from the controller chip set. This information is used by LAN Network Manager:
The following line displays Token Ring statistics. See the Token Ring specification for more information:
The following line indicates that Token Ring communication has been enabled on the interface. If this line of output appears, the message "Source Route Bridge capable" should appear in the show interfaces tokenring display.
Table 16, Part 2 describes the fields shown in the following line of sample output:
The following line is specific to the hardware:
In the following line, TX shorts are the number of packets the interface transmits that are discarded because they are smaller than the medium's minimum packet size. TX giants are the number of packets the interface transmits that are discarded because they exceed the medium's maximum packet size.
The following line indicates the state of the controller. Possible values include active, failure, inactive, and reset.
The following line displays detailed information relating to the monitor state shown in the previous line of output. This information relates to the firmware on the controller. This information is relevant to our engineers only if the monitor state is something other than active.
Table 16, Part 3 describes the fields in the following line or output:
| Field | Description |
|---|---|
|
Interface has not been configured for bridging, but it has that capability. |
The following line displays the version numbers for the kernel and the accelerator microcode of the Madge firmware on the board; this firmware is the LLC interface to the chip set:
The following line displays LAN Network Manager information that relates to ring status:
The following line corresponds to the functional address and the group address shown in show interfaces tokenring output:
The following line displays interface board state information that is proprietary:
The following lines display information that is proprietary. Our engineers use this information for debugging purposes:
Each of the fields in the following line maps to a field in the show source bridge display, as follows: ring maps to srn; bridge num maps to bn; target maps to trn; and max hops maps to max:
In the following lines of output, the number preceding the slash (/) indicates the count since the value was last displayed; the number following the slash (/) indicates count since the system was last booted:
In the following line, the number preceding the slash (/) indicates the count since the value was last displayed; the number following the slash (/) indicates count since the system was last booted. The runts and giants values that appear here correspond to the runts and giants values that appear in show interfaces tokenring output:
The following lines are receiver-specific information that our engineers can use for debugging purposes:
The following lines include very specific statistics that are not relevant in most cases, but exist for historical purposes. In particular, the internal errors, burst errors, ari/fci, abort errors, copy errors, frequency errors, dma bus errors, and dma parity errors fields are not relevant.
The following lines are low-level Token Ring interface statistics relating to the state and status of the Token Ring with respect to all other Token Rings on the line:
Use the show interfaces tokenring privileged EXEC command to display information about the Token Ring interface and the state of source-route bridging.
Syntax Description
|
(Optional) Interface number. If you do not provide a value, the command will display statistics for all Token Ring interfaces. |
Command Modes
Command History
Examples
The following is sample output from the show interfaces tokenring command:
Table 17 describes significant fields shown in the display.
Use the show lnm bridge privileged EXEC command to display all currently configured bridges and all parameters that are related to the bridge as a whole, not to one of its interfaces.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following is sample output from the show lnm bridge command:
Table 18 describes significant fields shown in the display.
| Field | Description |
|---|---|
|
Any LNM stations that are currently connected to this bridge. An entry preceded by an asterisk is the controlling LNM. | |
Use the show lnm config privileged EXEC command to display the logical configuration of all bridges configured in a router. This information is needed to configure an LNM Management Station to communicate with a router. This is especially important when the router is configured as a multiport bridge, thus employing the concept of a virtual ring.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following is sample output from the show lnm config command for a simple two-port bridge:
The following is sample output from the show lnm config command for a multiport bridge:
Table 19 describes significant fields shown in the display.
Use the show lnm interface privileged EXEC command to display all LNM-related information about a specific interface or all interfaces.
Syntax Description
Command Modes
Command History
Usage Guidelines
This command is for all types of interfaces, including Token Ring interfaces. If you want information specific to Token Ring, use the show lnm ring command.
Examples
The following is sample output from the show lnm interface command:
Table 20 describes significant fields shown in the display. See the show lnm station command for a description of the fields in the bottom half of the sample output.
Related Commands
Use the show lnm ring privileged EXEC command to display all LNM information about a specific Token Ring or all Token Rings. If a specific interface is requested, it also displays a list of all currently active stations on that interface.
Syntax Description
Command Modes
Command History
Usage Guidelines
The output of this command is the same as the output of the show lnm interface command. See the show lnm interface and show lnm station commands for sample output and a description of the fields. The same information can be obtained by using the show lnm interface command, but instead of specifying an interface number, you specify a ring number as an argument.
Related Commands
Use the show lnm station privileged EXEC command to display LNM-related information about a specific station or all known stations on all rings. If a specific station is requested, it also displays a detailed list of that station's current MAC-level parameters.
Syntax Description
Command Modes
Command History
Examples
The following is sample output from the show lnm station command when a particular address (in this case, 1000.5abc15) has been specified:
Table 21 describes significant fields shown in the display.
| 1The description of these error conditions can be found in the IBM Architecture Reference Manual. |
Use the show netbios-cache privileged EXEC command to display a list of NetBIOS cache entries.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following is sample output from the show netbios-cache command:
Table 22 describes significant fields shown in the display.
Related Commands
Use the show rif privileged EXEC command to display the current contents of the RIF cache.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following is sample output from the show rif command:
In the display, entries marked with an asterisk (*) are the router's interface addresses. Entries marked with a dash (-) are static entries. Entries with a number denote cached entries. If the RIF timeout is set to something other than the default of 15 minutes, the timeout is displayed at the top of the display. Table 23 describes significant fields shown in the display.
Related Commands
| Command | Description |
|---|---|
Use the show source-bridge privileged EXEC command to display the current source bridge configuration and miscellaneous statistics.
Syntax Description
Command Modes
Command History
Examples
The following is sample output from the show source-bridge command:
The following is sample output from the show source-bridge command when Token Ring LANE is configured.
The following is sample output from the show source-bridge command with the interface keyword specified.
Table 24 describes significant fields shown in the displays.
Use the show span EXEC command to display the spanning-tree topology known to the router.
Syntax Description
This command has no arguments or keywords.
Command Modes
Command History
Examples
The following is sample output from the show span command:
A port (spanRSRB) is created with each virtual ring group. The port will be disabled until one or more peers go into open state in the ring group.
Use the source-bridge interface configuration command to configure an interface for source-route bridging. Use the no form of this command to disable source-route bridging on an interface.
Syntax Description
Defaults
Command Modes
Command History
| Release | Modification |
|---|---|
Usage Guidelines
The parser automatically displays the word "active" in the source-bridge command in configurations that have SRB enabled. You do not need to enter the source-bridge command with the active keyword.
Examples
In the following example, Token Rings 129 and 130 are connected via a router:
In the following example, an FDDI ring on one router is connected to a Token Ring on a second router across a DLSw+ link:
In the following example, a router forwards frames from a locally attached Token Ring over the Frame Relay using SRB:
Related Commands
| Command | Description |
|---|---|
|
Assigns a DLCI to a specified Frame Relay subinterface on the router or access server. | |
Use the source-bridge connection-timeout global configuration command to establish the interval of time between first attempt to open a connection until a timeout is declared. Use the no form of this command to disable this feature.
Syntax Description
Defaults
The default connection-timeout interval is 10 seconds.
Command Modes
Command History
Usage Guidelines
The source-bridge connection-timeout command is used for setting timeout intervals in a complex topology such as a large multihop WAN with virtual rings or satellite links. The timeout interval is used when a connection to a remote peer is attempted. If the timeout interval expires before a response is received, the connection attempt is aborted.
Examples
The following example sets the connection timeout interval to 60 seconds:
Related Commands
| Command | Description |
|---|---|
Use the source-bridge enable-80d5 global configuration command to change the router's Token Ring to Ethernet translation behavior. Use the no form of this command to disable this function.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The Cisco IOS software supports two types of Token Ring LLC2 to Ethernet conversion. They are as follows:
Use this global configuration command to change the translation behavior. By default, the Cisco IOS software translates Token Ring LLC2 to Ethernet 802.3 LLC2. This command allows you to configure the software to translate Token Ring LLC2 frames into Ethernet 0x80d5 format frames.
This command is useful when you have a non-IBM device attached to an IBM network with devices that are using the nonstandard Token Ring LLC2 to Ethernet 80d5 translation. If you do not configure your router to enable 80d5 processing, the non-IBM and IBM devices will not be able to communicate.
The parameters specifying the current parameters for the processing of 0x80d5 frames are given at the end of the output of the show span command.
|
Note The 80d5 frame processing option is available only with SR/TLB. It is not available when source-route transparent bridging (SRT) is used. |
Use the show span to check whether 80d5 processing is enabled. If it is, the following line displays in the output:
Examples
The following example enables 0x80d5 processing, removes the translation for SAP 08, and adds the translation for SAP 1c:
Related Commands
Use the source-bridge explorer-dup-ARE-filter global configuration command to prevent excessive forwarding of explorers in networks with redundant topologies. Use the no form of this command to disable this feature.
Syntax Description
This command has no arguments or keywords.
Defaults
Duplicate explorer filtering is disabled.
Command Modes
Command History
Examples
The following example enables duplicate explorer filtering:
Use the source-bridge explorer-fastswitch global configuration command to enable explorer fast switching. To disable explorer fast switching, use the no form of this command.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
Use the no form of this command in conjunction with the source-bridge explorerq-depth and the source-bridge explorer-maxrate command to optimize explorer processing.
Examples
The following example enables explorer fast switching after it has been previously disabled:
Related Commands
| Command | Description |
|---|---|
Use the source-bridge explorer-maxrate global configuration command to set the maximum byte rate of explorers per ring. To reset the default rate, use the no form of this command.
Syntax Description
|
Number in the range 100 to 1000000000 (in bytes per second). The default maximum byte rate is 38400 bytes per second. |
Defaults
The default maximum byte rate is 38400 bytes per second.
Command Modes
Command History
Usage Guidelines
Given the number of different explorer packet types and sizes and the bandwidth limits of the various interfaces, the bus data rate (as opposed to the packet rate) is the common denominator used to decide when to flush incoming explorers. The packets are dropped by the interface before any other processing.
Examples
The following command sets the maximum byte rate of explorers on a ring:
Use the source-bridge explorerq-depth global configuration command to set the maximum explorer queue depth. To reset the default value, use the no form of this command.
Syntax Description
Defaults
The default maximum depth is 30.
Command Modes
Command History
Usage Guidelines
In this implementation, the limit is on a per-interface basis such that each interface can have up to the maximum (default 30) outstanding packets on the queue before explorers from that particular interface are dropped.
Examples
The following example sets the maximum explorer queue depth:
Use the source-bridge input-address-list interface configuration command to apply an access list to an interface configured for source-route bridging. This command filters source-routed packets received from the router interface based upon the source mac address. Use the no form of this command to remove the application of the access list.
Syntax Description
Defaults
Command Modes
Command History
Examples
The following example assigns access list 700 to Token Ring 0:
Related Commands
Use the source-bridge input-lsap-list interface configuration command to filter, on input, FDDI and IEEE 802-encapsulated packets that include the destination service access point (DSAP) and source service access point (SSAP) fields in their frame formats. The access list specifying the type codes to be filtered is given by this variation of the source-bridge interface configuration command.
Syntax Description
Defaults
Command Modes
Command History
Examples
The following example specifies access list 203:
Related Commands
Use the source-bridge input-type-list interface configuration command to filter SNAP-encapsulated packets on input.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
Use the access list command to specify type code when using the source-bridge input-type-list command.
Examples
The following example specifies access list 202:
Related Commands
| Command | Description |
|---|---|
|
Configures the access list mechanism for filtering frames by protocol type or vendor code. | |
Use the source-bridge max-hops interface configuration command to control the forwarding or blocking of all-routes explorer frames received on an interface. Use the no form of this command to reset the count to the maximum value.
Syntax Description
|
Determines the number of bridges an explorer packet can traverse. Typically, the maximum number of bridges for interoperability with IBM equipment is seven. |
Defaults
The maximum number of bridge hops is seven.
Command Modes
Command History
Usage Guidelines
Frames are forwarded only if the number of hops in the routing information field of the input frame plus hops appended by the router is less than or equal to the specified count. If the interface is connected to a destination interface, the router appends one hop. If the interface is tied to a virtual ring, the router appends two hops. This applies only to all-routes explorer frames on input to this interface.
Examples
The following example limits the maximum number of source-route bridge hops to five.
Related Commands
Use the source-bridge max-in-hops interface configuration command to control the forwarding or blocking of spanning-tree explorer frames received on an interface. Use the no form of this command to reset the count to the maximum value.
Syntax Description
|
Determines the number of bridges an explorer packet can traverse. Typically, the maximum number of bridges for interoperability with IBM equipment is seven. |
Defaults
The maximum number of bridge hops is seven.
Command Modes
Command History
Usage Guidelines
Frames are forwarded only if the number of hops in the routing information field of the input frame is less than or equal to the specified count. This applies only to spanning-tree explorer frames input to the specified interface.
Examples
The following example limits the maximum number of source-route bridge hops to three:
Related Commands
Use the source-bridge max-out-hops interface configuration command to control the forwarding or blocking of spanning-tree explorer frames sent from this interface. Use the no form of this command to reset the count to the maximum value.
Syntax Description
|
Determines the number of bridges an explorer packet can traverse. Typically, the maximum number of bridges for interoperability with IBM equipment is seven. |
Defaults
The maximum number of bridge hops is seven.
Command Modes
Command History
Usage Guidelines
Frames are forwarded only if the number of hops in the routing information field of the frame (including the hops appended by the router) is less than or equal to the specified count. This applies only to spanning-tree explorer frames output from the specified interface.
Examples
The following example limits the maximum number of source-route bridge hops to five:
Related Commands
Use the source-bridge output-address-list interface configuration command to apply an access list to an interface configured for source-route bridging. This command filters source-routed packets sent to the router interface based upon the destination mac address. Use the no form of this command to remove the application of the access list.
Syntax Description
Defaults
Command Modes
Command History
Examples
To disallow the bridging of Token Ring packets of all IBM workstations on Token Ring 1, use this sample configuration. The software assumes that all such hosts have Token Ring addresses with the vendor code 1000.5A00.0000. The vendor portion of the MAC address is the first three bytes (left to right) of the address. The first line of the access list denies access to all IBM workstations, while the second line permits access to all other devices on the network. Then, the access list can be assigned to the input side of Token Ring 1.
Related Commands
Use the source-bridge output-lsap-list interface configuration command to filter, on output, FDDI and IEEE 802-encapsulated packets that have destination service access point (DSAP) and source service access point (SSAP) fields in their frame formats.
Syntax Description
|
Number of the access list. This access list is applied just before sending out a frame to an interface. Specify zero (0) to disable the filter. The value must be in the range 200 to 299. |
Defaults
Command Modes
Command History
Usage Guidelines
The access list specifying the type codes to be filtered is given by this command.
Examples
The following example specifies access list 251:
Related Commands
Use the source-bridge output-type-list interface configuration command to filter SNAP-encapsulated frames by type code on output.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
Input and output type code filtering on the same interface reduces performance and is not recommended.
Access lists for Token Ring- and IEEE 802-encapsulated packets affect only source-route bridging functions. Such access lists do not interfere with protocols that are being routed.
Use the access list specifying the types codes in this command.
Examples
The following example filters SNAP-encapsulated frames on output:
Related Commands
| Command | Description |
|---|---|
|
Configures the access list mechanism for filtering frames by protocol type or vendor code. | |
Use the source-bridge proxy-explorer interface configuration command to configure the interface to respond to any explorer packets from a source node that meet the conditions described below. Use the no form of this command to cancel responding to explorer packets with proxy explorers.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
The proxy explorer function allows the source-route bridge interface to respond to a source node on behalf of a particular destination node. The interface responds with proxy explorers. The following conditions must be met in order for the interface to respond to a source node with proxy explorers on behalf of a destination node:
If all of the above conditions are met, the source-route bridge interface will turn the packet around, append the appropriate RIF, and reply to the source node.
Use proxy explorers to limit the amount of explorer traffic propagating through the source-bridge network, especially across low-bandwidth serial lines. The proxy explorer is most useful for multiple connections to a single node.
Examples
The following example configures the router to use proxy explorers on Token Ring 0:
Use the source-bridge proxy-netbios-only global configuration command to enable proxy explorers for the NetBIOS name-caching function. Use the no form of this command to disable the NetBIOS name-caching function.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Examples
The following example configures the router to use proxy explorers:
Use the source-bridge ring-group global configuration command to define or remove a ring group from the configuration. Use the no form of this command to cancel previous assignments.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
To configure a source-route bridge with more than two network interfaces, the ring group concept is used. A ring group is a collection of Token Ring interfaces in one or more routers that are collectively treated as a virtual ring. The ring group is denoted by a ring number that must be unique for the network. The ring group's number is used just like a physical ring number, showing up in any route descriptors contained in packets being bridged.
To configure a specific interface as part of a ring group, its target ring number parameter is set to the ring group number specified in this command. Do not use the number 0; it is reserved to represent the local ring.
To avoid an address conflict on the virtual MAC address, use a locally administered address in the form 4000.xxxx.xxxx.
Examples
In the following example, multiple Token Rings are source-route bridged to one another through a single router. These Token Rings are all part of ring group 7.
Related Commands
| Command | Description |
|---|---|
Use the source-bridge route-cache interface configuration command to enable fast switching. Use the no form of this command to disable fast switching.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
By default, fast-switching software is enabled in the source-route bridging software. Fast switching allows for faster implementations of local source-route bridging between 4/16-Mb Token Ring cards in the same router. This feature also allows for faster implementations of local source-route bridging between two routers using the 4/16-Mb Token Ring cards and the direct interface encapsulation.
Examples
The following example disables use of fast switching between two 4/16-Mb Token Ring interfaces:
Related Commands
| Command | Description |
|---|---|
Use the source-bridge route-cache cbus interface configuration command to enable autonomous switching. Use the no form of this command to disable autonomous switching.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
Autonomous switching in source-route bridging software is available for local source-route bridging between ciscoBus Token Ring cards in the same router. Autonomous switching provides higher switching rates than does fast-switching between 4/16-Mb Token Ring cards. Autonomous switching works for both two-port bridges and multiport bridges that use ciscoBus Token Ring cards.
In a virtual ring that includes both ciscoBus Token Ring and 4/16-MbToken Ring interfaces, frames that flow from one ciscoBus Token Ring interface to another are autonomously switched, and the remainder of the frames are fast switched. The switching that occurs on the ciscoBus Token Ring interface takes advantage of the high-speed ciscoBus controller processor.
|
Note Using either NetBIOS byte offset access lists or the access-expression capability to logically combine the access filters disables the autonomous or fast switching of SRB frames. |
Examples
The following example enables use of autonomous switching between two ciscoBus Token Ring interfaces:
Related Commands
| Command | Description |
|---|---|
Use the source-bridge route-cache sse interface configuration command to enable Cisco's silicon switching engine (SSE) switching function. Use the no form of this command to disable SSE switching.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Examples
The following example enables use of SSE switching between two 4/16-Mb Token Ring interfaces:
Related Commands
| Command | Description |
|---|---|
Use the source-bridge sap-80d5 global configuration command to allow non-IBM hosts (attached to a router with 80d5 processing enabled) to use the standard Token Ring to Ethernet LLC2 translation instead of the nonstandard Token Ring to Ethernet 80d5 translation. This command allows you to set the translation on a per-DSAP basis. Use the no form of this command to disable this feature.
Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
By default, the following DSAPs are enabled for 0x80d5 translation simply by specifying the source-bridge enable-80d5 command:
Any of these DSAPs can be disabled with the no form of this command.
The parameters specifying the current parameters for the processing of 0x80d5 frames are given at the end of the output of the show span command.
|
Note The 80d5 frame processing option is available only with SR/TLB. It is not available when source-route transparent bridging (SRT) is used. |
Use the show span to check whether 80d5 processing is enabled for a particular DSAP. The following line displays in the output if 80d5 processing is enabled, listing each DSAP for which it is enabled:
Examples
The following example enables 0x80d5 processing, removes the translation for SAP 08, and adds the translation for SAP 1c:
Related Commands
Use the automatic version of the source-bridge spanning interface configuration command to enable the automatic spanning-tree function for a specified group of bridged interfaces. Use the no source-bridge spanning command to return to the default disabled state. Use the no source-bridge spanning path-cost command to return an assigned path cost to the default path cost of 16.
Syntax Description
|
Number in the range 1 to 9 that
you choose to refer to a particular group of bridged interfaces. This must
be the same number as assigned in the | |
|
(Optional) Path cost for the interface. The valid range is 0 to 65535. |
Defaults
The automatic spanning-tree function is disabled. The default path cost is 16.
Command Modes
Command History
Examples
The following example adds Token Ring 0 to bridge group 1 and assigns a path cost of 12 to Token Ring 0:
Related Commands
| Command | Description |
|---|---|
|
Creates a bridge group that runs the automatic spanning-tree function. | |
|
Displays the current source bridge configuration and miscellaneous statistics. |
Use the source-bridge spanning interface configuration command to enable use of spanning explorers. The no form of this command disables their use. Only spanning explorers will be blocked; everything else will be forwarded.
Syntax Description
This command has no arguments or keywords.
Defaults
Command Modes
Command History
Usage Guidelines
Use of the source-bridge spanning command is recommended. This command puts the interface into a forwarding or active state with respect to the spanning tree. There are two types of explorer packets used to collect RIF information:
Examples
The following example enables use of spanning explorers:
Related Commands
Use the source-bridge transparent global configuration command to establish bridging between transparent bridging and source-route bridging. Use the no form of this command to disable a previously established link between a source-bridge ring group and a transparent bridge group.
Syntax Description
|
Virtual ring group created by the source-bridge ring-group command. This is the source-bridge virtual ring to associate with the transparent bridge group. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 to 4095. | |
|
Ring number used to represent the transparent bridging domain to the source-route bridged domain. This number must be a unique number, not used by any other ring in your source-route bridged network. | |
|
Bridge number of the bridge that leads to the transparent bridging domain. | |
|
Number of the transparent bridge group that you want to tie into your source-route bridged domain. The no form of this command disables this feature. | |
|
(Optional) Organizational unique identifier. Possible values include the following: |
Defaults
Command Modes
Command History
Usage Guidelines
Before using this command, you must have completely configured your router using multiport source-bridging and transparent bridging.
Specify the 90-compatible OUI when talking to our routers. This OUI provides the most flexibility. Specify the standard OUI when talking to IBM 8209 bridges and other vendor equipment. This OUI does not provide for as much flexibility as the other two choices. The cisco OUI is provided for compatibility with future equipment.
Do not use the standard OUI unless you are forced to interoperate with other vendor equipment, such as the IBM 8209, in providing Ethernet and Token Ring mixed media bridged connectivity. Only use the standard keyword when you are transferring data between IBM 8209 Ethernet/Token Ring bridges and routers running the SR/TLB software (to create a Token Ring backbone to connect Ethernets). Use of the standard keyword causes the OUI code in Token Ring frames to always be 0x000000. In the context of the standard keyword, an OUI of 0x000000 identifies the frame as an Ethernet Type II frame. If the OUI in Token Ring frame is 0x000000 SR/TLB will output an Ethernet Type II frame.
When 8209 compatibility is enabled with the ethernet transit-oui standard command, the SR/TLB chooses to translate all Token Ring SNAP frames into Ethernet Type II frames as described earlier in this chapter.
Examples
The following example establishes bridging between a transparent-bridge network and a source-route network:
Related Commands
| Command | Description |
|---|---|
Use the source-bridge transparent fastswitch global configuration command to enable fast switching of packets between the SRB and transparent domains. Use the no form of this command to disable fast switching of packets.
Syntax Description
|
Virtual ring group created by the source-bridge ring-group command. This is the source-bridge virtual ring to associate with the transparent bridge group. This ring group number must match the number you have specified with the source-bridge ring-group command. The valid range is 1 to 4095. | |
|
Fast-switched SR/TLB enables the Cisco IOS software to process packets at the interrupt level. |
Defaults
Fast-switched SR/TLB is enabled.
Command Modes
Command History
Usage Guidelines
Because fast-switched SR/TLB is enabled by default when the router is configured for SR/TLB, there are no user-specified changes to the operation of the router, and the enabling command does not appear in the configuration.
The no source-bridge transparent ring-group fastswitch command is provided to disable fast-switched SR/TLB, causing the router to handle packets by process switching. When fast-switched SR/TLB is disabled, the no form of the command appears on a separate line of the configuration, immediately below the parent source-bridge transparent command.
If fast-switch SR/TLB has been disabled, it can enabled using the source-bridge transparent ring-group fastswitch command, but the enabling form of the command will not appear in the configuration.
Examples
The following example disables fast-switched SR/TLB between a transparent-bridge network and a source-route network:
Related Commands
Command
Description
Posted: Fri Jan 17 03:47:35 PST 2003
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