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Cisco Catalyst 2600 Series Switches

TR-ISL Trunking Between Cisco Catalyst 5000 and 3900 Switches and Routers

Document ID: 12404

Updated: Sep 09, 2005

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Introduction

Token Ring Inter-Switch Linking (TR-ISL) is a point-to-point protocol that works between two Cisco devices (switches or routers) that support Inter-Switch Linking (ISL) on their 100 Mb Fast Ethernet interfaces. TR-ISL Trunk ports enable connections between Catalyst 5000, Catalyst 3900, and Cisco routers to carry Token Ring traffic from multiple Virtual Local Area Network (VLAN). Without TR-ISL trunking, a link between the switches or routers carries Token Ring traffic from one VLAN. TR-ISL trunking is not required in simple switched networks that contain only one VLAN (broadcast domain).

The two ways to configure TR-ISL trunking that are detailed in this document are:

  • How to enable IP routing between Catalyst 5000 Token Ring Bridge Relay Function (TrBRF) subnets, with the use of TR-ISL trunking to a Cisco 7200 router.

  • How to extend the TrBRF from a Catalyst 5000 to a Catalyst 3900 using TR-ISL trunking.

The examples show how to check the hardware modules and establish link-level connectivity between them. They also show how to configure the TrBRF and Token Ring Concentrator Relay Function (TrCRF) VLANs and how to use the spanning tree modes and MAC addresses stored in the internal tables to verify the network topologies.

The default Token Ring VLANs are 1003 and 1005. All Token Ring port boards plugged into the switch, by default, belong to TrCRF 1003. Default TrCRFs can not be distributed. However, an exception to this rule is default TrCRF 1003, which can be active in multiple switches.

When a TrCRF is active, it has ports assigned to it. Once you assign ports to a TrCRF, you can only use that TrCRF locally on the switch. If you assign the same TrCRF on multiple switches, the Duplicate Ring Protocol (DRiP) disables all ports on the offending TrCRF.

Prerequisites

Requirements

There are no specific requirements for this document.

Components Used

The information in this document is based on these software versions:

  • Cisco IOS?? Software Release 12.1(5)

  • Cisco IOS Catalyst 3900 Software Release 4.1(2)

  • Cisco IOS Catalyst 5000 Software Release 5.2(3)

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Conventions

For more information on document conventions, refer to the Cisco Technical Tips Conventions.

TR-ISL Between a Cisco Catalyst 5000 and a 72xx Router for Routing IP Traffic

In this example, two VLANs are defined on the Catalyst 5000 switch. A VLAN is the sum of a TrBRF and all of its children TrCRFs, in one bridged domain. In IP terms, it represents a major network or a subnet of the network. A router is not needed to connect between stations located on different TrCRFs that are joined to the same TrBRF. The TrBRF can bridge packets to all of its children TrCRFs that it joins. According to the rules of routing and bridging???defined by the seven layer Open System Interconnection (OSI) model???a Layer 3 device is necessary to route between the VLANs. One way to provide this routing is an external router. Only routers with 100 MB or faster Ethernet ports can implement TR-ISL VLAN trunking.

trisl3_01.gif

This hardware supports TR-ISL on Cisco routers:

  • 7500 and 7200 port adapters support TR-ISL. The 7500 supports Versatile Interface Processor (VIP)-15/20/40. VIP2-50 support was added in v12.0. 7200 TR-ISL support was added in v11.3(4)T.

    • Two-port Fast Ethernet 100BaseTX (PA-2FEISL-TX)

    • Two-port Fast Ethernet 100BaseFX (PA-2FEISL-FX)

    • One-port Fast Ethernet 100BaseTX (PA-2FEISL-TX)

    • One-port Fast Ethernet 100BaseFX (PA-2FEISL-FX)

  • 3600 port adapters support TR-ISL at 100 Mbps with and without the integrated channel service unit (CSU) and data service unit (DSU). Due to a hardware restriction on one of the older chips, TR-ISL is not supported on one-port Fast Ethernet network module 10/100BaseTX, NM-1FE-TX, and NM-1FE-TX. TR-ISL support was introduced on the 3600 with v12.0(3)T.

    • NM-1FE-1CT1

    • NM-1FE-2CT1

    • NM-1FE-1CE1

    • NM-1FE-2CE1

    • NM-1FE1R2W

  • 2600 supports TR-ISL with the integrated Fast Ethernet ports on the 2620 and 2621. TR-ISL support was introduced on the 2600 with v12.0(3)T.

Enabling IP Routing Between Catalyst 5000 TrBRF Subnets Using TR-ISL Trunking to a Cisco 7200 Router

  1. Ensure that you are using the right hardware on the 7200 router:

    Burak# show diag
    
    Slot 6:
            Fastethernet (FX-ISL) Port adapter, 2 ports
            Port adapter is analyzed
            Port adapter insertion time 00:36:03 ago
            EEPROM contents at hardware discovery:
            Hardware revision 1.2           Board revision B0
            Serial number     12391860      Part number    73-2619-02
            Test history      0x3           RMA number     00-00-00
            EEPROM format version 1
            EEPROM contents (hex):
              0x20: 01 6D 01 02 00 BD 15 B4 49 0A 3B 02 03 00 00 00
              0x30: 58 00 00 00 99 03 08 00 00 00 FF FF FF FF FF 00

    Fields for which to look:

  2. The ISL Fast Ethernet port 6/0 on the 7200 router is connected to the 100BaseFX multimode (MM) Ethernet module 5, port 1 on the Catalyst 5000. The Catalyst 5000 can run ISL trunking. Check the installed modules on the Catalyst 5000.

    OB (enable) show modules
    
    Mod Slot Ports Module-Type               Model               Status
    --- ---- ----- ------------------------- ------------------- --------
    1   1    2     10/100BaseTX Supervisor   WS-X5530            ok
    2   2    12    100BaseFX MM Ethernet     WS-X5111            ok
    3   3    16    Token Ring                WS-X5030            ok
    5   5    12    100BaseFX MM Ethernet     WS-X5201            ok
    
    Mod Module-Name         Serial-Num
    --- ------------------- --------------------
    1                       00011441228
    2                       00005857899
    3                       00007383165
    5                       00007809789
    
    Mod MAC-Address(es)                        Hw     Fw         Sw
    --- -------------------------------------- ------ ---------- --------
    1   00-90-2b-6a-f0-00 to 00-90-2b-6a-f3-ff 2.0    3.1.2      5.2(3)
    2   00-e0-b0-a3-44-a4 to 00-e0-b0-a3-44-af 1.4    1.3        5.2(3)
    3   00:05:77:13:67:74 to 00:05:77:13:67:84 1.1    1.0(117)   3.2(5)
    5   00-e0-1e-b6-ef-54 to 00-e0-1e-b6-ef-5f 2.0    3.1(1)     5.2(3)
    
    Mod Sub-Type Sub-Model Sub-Serial Sub-Hw
    --- -------- --------- ---------- ------
    1   NFFC     WS-F5521  0010435278 1.1
    1   uplink   WS-U5531  0007438033 1.1
  3. Check the capabilities of the ISL module that is installed in module 5, port 1 (port 5/1) on the Catalyst 5000.

    OB (enable) show port capabilities 5/1
    
    Model                    WS-X5201
    Port                     5/1
    Type                     100BaseFX MM
    Speed                    100
    Duplex                   half,full
    Trunk encap type         ISL
    Trunk mode               on,off,desirable,auto,nonegotiate
    Channel                  5/1-2,5/1-4
    Broadcast suppression    pps(0-150000),percentage(0-100)
    Flow control             no
    Security                 yes
    Membership               static,dynamic
    Fast start               yes
    QOS                      n/a
    QOS classification       none
    Rewrite                  no
    UDLD                     Capable

    Fields for which to look:

    • Port can run 100 Mb or higher.

    • Port supports full duplex operation.

  4. Configure the 100BaseFX MM Ethernet port 5/1 on the Catalyst 5000 for full duplex with ISL trunking.

    OB (enable) set port duplex 5/1 full
    
    Port(s)  5/1 set to full-duplex.
    
    OB (enable) set trunk 5/1 isl on
    
    Port(s)  5/1 trunk mode set to on.
    Port(s)  5/1 trunk type set to Isl.
  5. Ensure that port 5/1 is configured for full duplex, 100 Mb, and ISL trunk.

    OB (enable) show port 5/1
    
    Port  Name               Status     Vlan       Level  Duplex Speed Type
    ----- ------------------ ---------- ---------- ------ ------ ----- ------------
    5/1                      connected  trunk      normal   full   100 100BaseFX MM
    
    Port  Security Violation Shutdown-Time Age-Time Max-Addr Trap     IfIndex
    ----- -------- --------- ------------- -------- -------- -------- -------
    5/1  disabled  shutdown             0        0        1 disabled     371
    
    Port  Num-Addr Secure-Src-Addr   Age-Left Last-Src-Addr     Shutdown/Time-Left
    ----- -------- ----------------- -------- ----------------- ------------------
    5/1         0                 -        -                 -        -         -
    
    Port     Broadcast-Limit Broadcast-Drop
    -------- --------------- --------------
    5/1                   -              -
    
    Port  Status     Channel              Admin Ch
                     Mode                 Group Id
    ----- ---------- -------------------- ----- -----
    5/1  connected  auto non-silent          5     0
    
    Port  Align-Err  FCS-Err    Xmit-Err   Rcv-Err    UnderSize
    ----- ---------- ---------- ---------- ---------- ---------
    5/1           0          0          0          0         0
    
    Port  Single-Col Multi-Coll Late-Coll  Excess-Col Carri-Sen Runts     Giants
    ----- ---------- ---------- ---------- ---------- --------- --------- ---------
    5/1           0          0          0          0         0         0         -
    
    Last-Time-Cleared
    --------------------------
    Mon Jan 15 2001, 09:09:22
  6. Configure TrBRF 500 and 600, and children TrCRFs 501, 510, 601, 610 VLANs, on the Catalyst 5000. Each TrBRF and its children TrCRFs that it joins represent an IP subnet. The 7200 router is needed to route from the TrBRF 500 subnet to the TrBRF 600 subnet.

    OB (enable) set vlan 500 name subnet1 type trbrf bridge 5
    
    Vlan 500 configuration successful
    
    OB (enable) set vlan 501 name ring1 type trcrf parent 500 ring 1 mode srb
    
    Vlan 501 configuration successful
    
    OB (enable) set vlan 510 name router1 type trcrf parent 500 ring 10 mode srb
    
    Vlan 510 configuration successful
    
    OB (enable) set vlan 600 name subnet2 type trbrf bridge 6
    
    Vlan 600 configuration successful
    
    OB (enable) set vlan 601 name ring2 type trcrf parent 600 ring 2 mode srb
    
    Vlan 601 configuration successful
    
    OB (enable) set vlan 610 name router2 type trcrf parent 600 ring 10 mode srb
    
    Vlan 610 configuration successful
  7. Ensure that the newly configured VLANs run over the correct ISL trunk on the Catalyst 5000.

    OB (enable) show trunk
    
    Port      Mode         Encapsulation  Status        Native vlan
    --------  -----------  -------------  ------------  -----------
    5/1       on           isl            trunking      1
    
    Port      Vlans allowed on trunk
    --------  ---------------------------------------------------------------------
    5/1       1-1005
    
    Port      Vlans allowed and active in management domain 
    --------  ---------------------------------------------------------------------
    5/1       1,480-481,500-501,510,600-601,610,700-702,804,806,902,1003,1005
    
    Port      Vlans in spanning tree forwarding state and not pruned
    --------  ---------------------------------------------------------------------
    5/1       1,480-481,500-501,510,600-601,610,700-702,804,806,902,1003,1005
  8. TrCRF 501 and TrCRF 601 represent the VLANs to which the Token Ring ports on the Catalyst 5000 connect. Configure Token Ring ports 3/1 through 3/8 to TrCRF 501, and configure Token Ring ports 3/9 through 3/16 to TrCRF 601.

    OB (enable) set vlan 501 3/1-8
    
    VLAN 501 modified.
    VLAN 1003 modified.
    VLAN  Mod/Ports
    ---- -----------------------
    501   3/1-8
          5/1
    
    OB (enable) set vlan 601 3/9-16
    
    VLAN 601 modified.
    VLAN 1003 modified.
    VLAN 701 modified.
    VLAN  Mod/Ports
    ---- -----------------------
    601   3/9-16
          5/1

    Two Source-Route Bridging (SRB) domains are now configured with Token Ring ports 3/1 through 3/8 assigned to TrCRF 501 and with Token Ring ports 3/9 through 3/16 assigned to TrCRF 601.

    OB (enable) show vlan
    
    VLAN Name                             Status    IfIndex Mod/Ports, Vlans
    ---- -------------------------------- --------- ------- --------------------
    1    default                          active    5       1/1-2
                                                            2/1-12
                                                            5/2-12
    500  subnet1                          active    386     386     501, 510
    501  ring1                            active    387     3/1-8
    510  router1                          active    388
    600  subnet2                          active    389     389     601, 610
    601  ring2                            active    390     3/9-16
    610  router2                          active    391
    
    1002 fddi-default                     active    6
    1003 trcrf-default                    active    9
    1004 fddinet-default                  active    7
    1005 trBrf-default                    active    8       8       1003
    
    VLAN Type  SAID       MTU   Parent RingNo BrdgNo Stp  BrdgMode Trans1 Trans2
    ---- ----- ---------- ----- ------ ------ ------ ---- -------- ------ ------
    1    enet  100001     1500  -      -      -      -    -        0      0
    500  trbrf 100500     4472  -      -      0x5    ibm  -        0      0
    501  trcrf 100501     4472  500    0x1    -      -    srb      0      0
    510  trcrf 100510     4472  500    0x10   -      -    srb      0      0
    600  trbrf 100600     4472  -      -      0x6    ibm  -        0      0
    601  trcrf 100601     4472  600    0x2    -      -    srb      0      0
    610  trcrf 100610     4472  600    0x10   -      -    srb      0      0
    
    1002 fddi  101002     1500  -      -      -      -    -        0      0
    1003 trcrf 101003     4472  1005   0xccc  -      -    srb      0      0
    1004 fdnet 101004     1500  -      -      0x0    ieee -        0      0
    1005 trbrf 101005     4472  -      -      0xf    ibm  -        0      0
    
    VLAN DynCreated
    ---- ----------
    1    static
    500  static
    501  static
    510  static
    600  static
    601  static
    610  static
    1002 static
    1003 static
    1004 static
    1005 static
    
    VLAN AREHops STEHops Backup CRF 1q VLAN
    ---- ------- ------- ---------- -------
    501  7       7       off
    510  7       7       off
    601  7       7       off
    610  7       7       off
    1003 7       7       off
    
    OB (enable) ping 2.2.2.254
    
    no answer from 2.2.2.254
  9. The 7200 router should be configured to route IP traffic from TrBRF 500 to TrBRF 600. You need only configure full-duplex on the on the 7200 router???s Fast Ethernet interface, to establish the link.

    Burak# conf t
    
    Burak(config)# interface fa 6/0
    
    Burak(config-if)# full-duplex
    
    Burak(config-if)# no shut
    
    Burak(config-if)# end
    
  10. Ensure that the Fast Ethernet ISL module 6/0 on the 7200 is up.

    Burak# show interface fa 6/0
    
    FastEthernet6/0 is up, line protocol is up
      Hardware is AmdFE, address is 00d0.bc33.cca8 (bia 00d0.bc33.cca8)
      MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
         reliability 255/255, txload 1/255, rxload 1/255
      Encapsulation ARPA, loopback not set
      Keepalive set (10 sec)
      Full-duplex, 100Mb/s, 100BaseTX/FX
      ARP type: ARPA, ARP Timeout 04:00:00
      Last input 00:00:04, output 00:00:06, output hang never
      Last clearing of "show interface" counters never
      Queueing strategy: fifo
      Output queue 0/40, 0 drops; input queue 0/75, 0 drops
      5 minute input rate 1000 bits/sec, 1 packets/sec
      5 minute output rate 0 bits/sec, 0 packets/sec
         6 packets input, 762 bytes
         Received 6 broadcasts, 0 runts, 0 giants, 0 throttles
         0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
         0 watchdog
         0 input packets with dribble condition detected
         4 packets output, 1173 bytes, 0 underruns(0/0/0)
         0 output errors, 0 collisions, 1 interface resets
         0 babbles, 0 late collision, 0 deferred
         0 lost carrier, 0 no carrier
         0 output buffer failures, 0 output buffers swapped out
  11. Create subinterfaces for the TrBRF 500 and TrBRF 600 subnets, to configure TR-ISL encapsulation. TrCRF 510 and TrCRF 610 are used to terminate the Routing Information Fields (RIFs) on the 7200 router. TrCRF 510 and TrCRF 610 are only used on the router. Do not assign ports to these TrCRFs. The Catalyst 5000 switch sees these TrCRFs as being used remotely.

    The VLAN configurations on the 7200 router must be consistent with the definitions on the Catalyst 5000 switch. Because the 7200 router does not support Virtual Terminal Protocol (VTP), the VLAN details on the command line should be specified. Convert the hexadecimal format of the bridge and ring numbers on the Catalyst 5000 to the decimal format on the 7200 router. You can also enter the ring number in hexadecimal if you precede it with 0x. For example, ring 16 decimal can be entered as 0x10 in hexadecimal.

    Note: When the configuration is displayed, the ring number appears in decimal, not hexadecimal. If you enter 0x10 in the configuration, ring 16 displays in the configuration.

    Burak(config)# conf t
    
    Burak(config)# interface fa 6/0.500
    
    Burak(config-subif)# encapsulation TR-ISL trbrf-vlan 500 bridge-num 5
    
    Burak(config-subif)# ip address 1.1.1.254 255.0.0.0
    
    Burak(config-subif)# multiring trcrf-vlan 510 ring 0x10
    
    Burak(config-subif)# multiring all
    
    Burak(config-subif)# mtu 4472
    
    Burak(config-subif)# interface fa 6/0.600
    
    Burak(config-subif)# encapsulation TR-ISL trbrf-vlan 600 bridge-num 6
    
    Burak(config-subif)# ip address 2.2.2.254 255.0.0.0
    
    Burak(config-subif)# multiring trcrf-vlan 610 ring 0x10
    
    Burak(config-subif)# multiring all
    
    Burak(config-subif)# mtu 4472
    
    Burak(config-subif)# exit
    
    Burak(config)# router rip
    
    Burak(config-router)# network 1.0.0.0
    
    Burak(config-router)# network 2.0.0.0
    
    Burak(config-router)# end
    
    Burak#
  12. Check the VLANs configured on the 7200 router.

    Burak# show vlan
    
    Virtual LAN ID:  1 (Inter Switch Link Encapsulation)
    
       vLAN Trunk Interface:   FastEthernet6/0
    
       Protocols Configured:   Address:          Received:    Transmitted:
    
    Virtual LAN ID:  600 (Inter Switch Link Encapsulation)
    
       vLAN Trunk Interface:   FastEthernet6/0.600
    
       Protocols Configured:   Address:          Received:    Transmitted:
               IP              2.2.2.254                0               0
    
    Virtual LAN ID:  610 (Inter Switch Link Encapsulation)
    
       vLAN Trunk Interface:   FastEthernet6/0.600
    
       Protocols Configured:   Address:          Received:    Transmitted:
               IP              2.2.2.254                0              12
    
    Virtual LAN ID:  500 (Inter Switch Link Encapsulation)
    
       vLAN Trunk Interface:   FastEthernet6/0.500
    
       Protocols Configured:   Address:          Received:    Transmitted:
               IP              1.1.1.254                0               0
    
    Virtual LAN ID:  510 (Inter Switch Link Encapsulation)
    
       vLAN Trunk Interface:   FastEthernet6/0.500
    
       Protocols Configured:   Address:          Received:    Transmitted:
               IP              1.1.1.254                0               6

    TrBRF 500 and TrBRF 600 subnets on the Catalyst 5000 can now use TrCRF 510 and TrCRF 610 on the 7200 router to terminate the RIF and route IP traffic between them. TrBRF 500 and TrBRF 600 drop frames that do not have a RIF. These frames are limited to TrCRF 501 and TrCRF 601 on the Catalyst 5000 to which the Token Ring end stations connect. The frames are also attached to the TrBRF 500 and TrBRF 600.

    Note: Refer to the TRISL Configuration Examples in Configuring Token Ring Inter-Switch Link for sample configurations of non-RIF traffic.

    Remember that the bridge and ring numbers are in hexadecimal on the Catalyst 5000 and that you must convert them to decimal on the 7200 router.

  13. Ensure that the 100BaseFX MM Ethernet subinterfaces on the 7200 router are up and that the maximum transmission unit (MTU) size is set to 4472 bytes.

    Burak# show interface fa 6/0.500
    
    FastEthernet6/0.500 is up, line protocol is up 
      Hardware is AmdFE, address is 00d0.bc33.cca8 (bia 00d0.bc33.cca8)
      Internet address is 1.1.1.254/8
      MTU 4472 bytes, BW 100000 Kbit, DLY 100 usec, 
         reliability 255/255, txload 1/255, rxload 1/255
      Encapsulation ISL Virtual LAN, Color 500.
      ARP type: SNAP, ARP Timeout 04:00:00
    
    Burak# show interface fa 6/0.600
    
    FastEthernet6/0.600 is up, line protocol is up 
      Hardware is AmdFE, address is 00d0.bc33.cca8 (bia 00d0.bc33.cca8)
      Internet address is 2.2.2.254/8
      MTU 4472 bytes, BW 100000 Kbit, DLY 100 usec, 
         reliability 255/255, txload 1/255, rxload 1/255
      Encapsulation ISL Virtual LAN, Color 600.
      ARP type: SNAP, ARP Timeout 04:00:00
  14. Check the Spanning-Tree modes on TrBRF 500 and TrCRF 501 on the Catalyst 5000. If the BRF is configured for SRB, then it must run the IBM Spanning-Tree. If the BRF is configured for source-route transparent bridging (SRT), then it must run the IEEE Spanning-Tree.

    If the BRF runs the IBM Spanning-Tree, the CRF can run either the IEEE or the Cisco Spanning-Tree. However, the default is the IEEE Spanning-Tree. If the BRF runs the IEEE Spanning-Tree, the CRF must run the Cisco Spanning-Tree.

    When the default mode is used on the Catalyst 5000, the IBM Spanning-Tree runs on TrBRF 500 and the IEEE Spanning-Tree runs on TrCRF 501.

    There are two types of explorers, all route explorers (ARE) and spanning-tree explorers (STE). The IBM Spanning-Tree only works on STEs. Follow the path of a STE to predict the state in which the Token Ring ports need to be, to forward the STE. The Spanning-Tree that is running on TrCRF 501 and TrCRF 601 deals exclusively with physical ports. Ensure that the correct ports are forwarding on TrCRF 501.

    OB (enable) show spantree 501
    
    VLAN 501
    Spanning tree enabled
    Spanning tree type          ieee
    
    Designated Root             00-90-2b-6a-f1-f4
    Designated Root Priority    32768
    Designated Root Cost        0
    Designated Root Port        1/0
    Root Max Age   10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Bridge ID MAC ADDR          00-90-2b-6a-f1-f4
    Bridge ID Priority          32768
    Bridge Max Age 10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Port                     Vlan Port-State    Cost  Priority Portfast   Channel_id
    ------------------------ ---- ------------- ----- -------- ---------- ----------
    3/1                     501  forwarding       62       32 disabled   0         
    3/2                     501  not-connected   250       32 disabled   0         
    3/3                     501  not-connected   250       32 disabled   0         
    3/4                     501  not-connected   250       32 disabled   0         
    3/5                     501  not-connected   250       32 disabled   0         
    3/6                     501  not-connected   250       32 disabled   0         
    3/7                     501  not-connected   250       32 disabled   0         
    3/8                     501  not-connected   250       32 disabled   0         
    5/1                     501  forwarding*      19       32 disabled   0         
    * = portstate set by user configuration or set by vlan 500 spanning tree.

    Frames enter from the end station that is attached to Token Ring port 3/1 assigned to TrCRF 501. Ensure that the TrCRF 501 port is forwarding. The IEEE Spanning-Tree runs in TrCRF 501 and affects all frames. Ensure that the TrCRF 501 passes explorer frames to TrBRF 601. Frames without a RIF field are blocked. There is a virtual connection between TrCRF 501 and TrBRF 500. Check the Spanning-Tree for TrBRF 500 to verify that the virtual connection is forwarding. IBM Spanning-Tree runs on TrBRF 500 and controls the virtual connection to TrCRF 501 and the ISL ports through which it trunks to reach the 7200 router. The IBM Spanning-Tree permits only STEs to be forwarded:

    OB (enable) show spantree 500
    
    VLAN 500
    Spanning tree enabled
    Spanning tree type          ibm
    
    Designated Root             00-90-2b-6a-f1-f3
    Designated Root Priority    32768
    Designated Root Cost        0
    Designated Root Port        1/0
    Root Max Age   10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Bridge ID MAC ADDR          00-90-2b-6a-f1-f3
    Bridge ID Priority          32768
    Bridge Max Age 10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Port,Vlan                Vlan Port-State    Cost  Priority Portfast   Channel_id
    ------------------------ ---- ------------- ----- -------- ---------- ----------
    5/1                     500  forwarding       19        4 disabled   0         
    501                     500  forwarding       62        4 disabled
    510                     500  inactive         62        4 disabled
    * = portstate set by user configuration.

    TR-ISL expands the TrBRF to include the TR-ISL attached router. This expansion happens on port 5/1. If frames need to travel across the expanded TR-ISL link, then ISL port 5/1 needs to forward. ISL port 5/1 forwards on the Spanning-Tree output of TrCRF 501 and TrBRF 500. However, if TrBRF 500 forwards ISL port 5/1, then TrBRF 500 forces the same forward state on TrCRF 501.

    Because no ports are assigned, TrCRF 510 is listed as inactive and the TrBRF 500 Spanning-Tree treats the TrCRF 510 as inactive. TrCRF 510 is used to terminate the RIF on the TR-ISL-attached router. The previous Spanning-Tree displays have verified that the STE frames can reach the 7200 router interface. Ensure that TrBRF 600 and TrCRF 601 can forward their STEs.

    OB (enable) show spantree 601
    
    VLAN 601
    Spanning tree enabled
    Spanning tree type          ieee
    
    Designated Root             00-90-2b-6a-f2-58
    Designated Root Priority    32768
    Designated Root Cost        0
    Designated Root Port        1/0
    Root Max Age   10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Bridge ID MAC ADDR          00-90-2b-6a-f2-58
    Bridge ID Priority          32768
    Bridge Max Age 10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Port                     Vlan Port-State    Cost  Priority Portfast   Channel_id
    ------------------------ ---- ------------- ----- -------- ---------- ----------
    3/9                     601  not-connected   250       32 disabled   0         
    3/10                    601  not-connected   250       32 disabled   0         
    3/11                    601  not-connected   250       32 disabled   0         
    3/12                    601  not-connected   250       32 disabled   0         
    3/13                    601  not-connected   250       32 disabled   0         
    3/14                    601  not-connected   250       32 disabled   0         
    3/15                    601  not-connected   250       32 disabled   0         
    3/16                    601  forwarding       62       32 disabled   0         
    5/1                     601  forwarding*      19       32 disabled   0         
    * = portstate set by user configuration or set by vlan 600 spanning tree.
    
    OB (enable) show spantree 600
    
    VLAN 600
    Spanning tree enabled
    Spanning tree type          ibm
    
    Designated Root             00-90-2b-6a-f2-57
    Designated Root Priority    32768
    Designated Root Cost        0
    Designated Root Port        1/0
    Root Max Age   10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Bridge ID MAC ADDR          00-90-2b-6a-f2-57
    Bridge ID Priority          32768
    Bridge Max Age 10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Port,Vlan                Vlan Port-State    Cost  Priority Portfast   Channel_id
    ------------------------ ---- ------------- ----- -------- ---------- ----------
    5/1                     600  forwarding       19        4 disabled   0         
    601                     600  forwarding       62        4 disabled
    610                     600  inactive         62        4 disabled
    * = portstate set by user configuration.
  15. Issue the ping command to check the IP routing between Token Ring end end stations that connect the TrCRF 501 to the TrBRF 500 subnet, and to check the Token Ring end stations that connect the TrCRF 601 to the TrBRF 600 subnet.

    Check the cache on the 7200 router to ensure that the MAC addresses have learned to use the correct ISL port and Token Ring VLANs.

    Burak# show rif
    
    Codes: * interface, - static, + remote
    
    Dst HW Addr    Src HW Addr    How   Idle(min) Vlan Routing Information Field
    00d0.bc33.cca8 N/A            Fa6/0.500   *    500 -
    00d0.bc33.cca8 N/A            Fa6/0.600   *    600 -
    4000.8787.8787 N/A            Fa6/0.600   0    601 0630.0106.0020
    0000.304a.4fc2 N/A            Fa6/0.500   0    501 0630.0105.0010
    

    Cached RIF entries are on the router. MAC address 0000.304a.4fc2 has been learned from TrCRF 501, and MAC address 4000.8787.8787 has been learned from TrCRF 601. This matches the desired network topology. From the breakdown of the RIFs, verify the ring and bridge numbers that the explorer passes, and ensure that the 4472 byte frames are supported over the ISL trunk. The 7200 router dynamically learns VLANs that are configured to run over this trunk. Remember that VTP is not supported on the 7200 router. For more information on RIF decode, refer to Understanding and Troubleshooting Local Source-Route Bridging.

  16. Check the VLANs that the router considers l-active (local configured) and r-active (dynamically learned). TrCRF 510 and TrCRF 610 should be local and should be used for RIF termination. TrCRF 501 and TrCRF 601 should be remote and should be used to connect the Token Ring end stations on the Catalyst 5000.

    Burak# show drip
    
    DRIP Database
    --------------------------------------------------
    Mac Address 00D0-BC33-CCA8
      Vlan     510    Status    30 : l-active, l-config,
      Vlan     610    Status    30 : l-active, l-config,
    
    Mac Address 0090-2B6A-F000
      Vlan     501    Status    0C : r-active, r-config,
      Vlan     601    Status    0C : r-active, r-config,
    
    Statitics:
    Advertisements received            2453
    Advertisements processed           9
    Advertisements transmitted         2451
    Last revision transmitted          0x994
    Last changed revision transmitted  0x7
  17. Check the Content Addressable Memory (CAM) table on the Catalyst 5000, to verify the MAC addresses.

    OB (enable) show cam dynamic
    
    * = Static Entry. + = Permanent Entry. # = System Entry. R = Router Entry.
    X = Port Security Entry
    
    VLAN  Dest MAC/Route Des    [CoS]  Destination Ports or VCs / [Protocol Type] 
    ----  ------------------    -----  -------------------------------------------
    1     00-d0-bc-33-cc-a8             5/1 [ALL]
    610   00:d0:bc:33:cc:a8             5/1
    510   00:d0:bc:33:cc:a8             5/1
    501   00:00:30:4a:4f:c2             3/1
    601   40:00:87:87:87:87             3/16
    Total Matching CAM Entries Displayed = 5

    MAC address 4000.8787.8787 is learned by TrCRF 601, and MAC address 0000.304a.4fc2 is learned by TrCRF 501. MAC address 00d0.bc33.cca8 of the Fast Ethernet ISL card on the 7200 router is learned from the TrCRF 510 and from the TrCRF 610 on the 7200 router. This matches the desired network topology. The TR-ISL configuration is complete.

Troubleshooting

There are many different types of TR-ISL configurations. A good way to troubleshoot them is to check the Spanning-Tree settings and the MAC address entries.

When you are troubleshooting, remember that a MAC address that is learned from the wrong port causes most problems.

Extending the TrBRF from a Catalyst 5000 to a Catalyst 3900 Using TR-ISL trunking

In this example, a Catalyst 5000 is connected to a Catalyst 3900 with a TR-ISL trunk. The TrBRF is then expanded over both switches, to permit SRB Token Ring end stations on both switches to connect to each other.

trisl3_02.gif

The Catalyst 3900 supports only ISL trunking and is hard-coded to run full duplex at 100 Mb. It expects any switch or external router, to which the trunk ports connect, to be configured for these options. The only configurable option on the Catalyst 3900 is to disable or enable the ISL port.

trisl3_03.gif

ISL port 21 on the Catalyst 3900 is connected to 100BaseFX MM Ethernet port 5/1 on the Catalyst 5000, which can run ISL trunking.

OB (enable) show modules

Mod Slot Ports Module-Type               Model               Status
--- ---- ----- ------------------------- ------------------- --------
1   1    2     10/100BaseTX Supervisor   WS-X5530            ok
2   2    12    100BaseFX MM Ethernet     WS-X5111            ok
3   3    16    Token Ring                WS-X5030            ok
5   5    12    100BaseFX MM Ethernet     WS-X5201            ok

Mod Module-Name         Serial-Num
--- ------------------- --------------------
1                       00011441228
2                       00005857899
3                       00007383165
5                       00007809789

Mod MAC-Address(es)                        Hw     Fw         Sw
--- -------------------------------------- ------ ---------- -------------
1   00-90-2b-6a-f0-00 to 00-90-2b-6a-f3-ff 2.0    3.1.2      5.2(3)
2   00-e0-b0-a3-44-a4 to 00-e0-b0-a3-44-af 1.4    1.3        5.2(3)
3   00:05:77:13:67:74 to 00:05:77:13:67:84 1.1    1.0(117)   3.2(5)
5   00-e0-1e-b6-ef-54 to 00-e0-1e-b6-ef-5f 2.0    3.1(1)     5.2(3)

Mod Sub-Type Sub-Model Sub-Serial Sub-Hw
--- -------- --------- ---------- ------
1   NFFC     WS-F5521  0010435278 1.1
1   uplink   WS-U5531  0007438033 1.1

Extending the TrBRF from a Catalyst 5000 to a Catalyst 3900 Using TR-ISL Trunking

  1. Set port 5/1 on the Catalyst 5000 to full duplex with ISL trunking.

    OB (enable) set port duplex 5/1 full
    
    Port(s)  5/1 set to full-duplex.
    
    OB (enable) set trunk 5/1 isl on
    
    Port(s)  5/1 trunk mode set to on.
    Port(s)  5/1 trunk type set to Isl.
  2. Issue the show port 5/1 command, to confirm that the Catalyst 5000 is set for full duplex, 100 Mb, and ISL trunk.

    OB (enable) show port 5/1
    
    Port  Name               Status     Vlan       Level  Duplex Speed Type
    ----- ------------------ ---------- ---------- ------ ------ ----- ------------
    5/1                      connected  trunk      normal   full   100 100BaseFX M
    
    Port  Security Violation Shutdown-Time Age-Time Max-Addr Trap     IfIndex
    ----- -------- --------- ------------- -------- -------- -------- -------
    5/1   disabled  shutdown             0        0        1 disabled     371
    
    Port  Num-Addr Secure-Src-Addr   Age-Left Last-Src-Addr     Shutdown/Time-Left
    ----- -------- ----------------- -------- ----------------- ------------------
    5/1         0                 -        -                 -        -         -
    
    Port     Broadcast-Limit Broadcast-Drop
    -------- --------------- --------------
    5/1                   -              -
    
    Port  Status     Channel              Admin Ch
                     Mode                 Group Id
    ----- ---------- -------------------- ----- -----
    5/1   connected  auto non-silent          5     0
    
    Port  Align-Err  FCS-Err    Xmit-Err   Rcv-Err    UnderSize
    ----- ---------- ---------- ---------- ---------- ---------
    5/1           0          0          0          0         0
    
    Port  Single-Col Multi-Coll Late-Coll  Excess-Col Carri-Sen Runts     Giants
    ----- ---------- ---------- ---------- ---------- --------- --------- ---------
    5/1           0          0          0          0         0         0         -
    
    Last-Time-Cleared
    --------------------------
    Mon Jan 15 2001, 09:09:22
  3. Ensure that port 2/1 is set for full duplex, 100 Mb, and ISL trunk.

    trisl3_04.gif

  4. Configure TrBRF 700 and its children TrCRF 701 through 702 Token Ring VLANs on the Catalyst 5000.

    OB (enable) set vlan 700 type trbrf bridge 5
    
    Vlan 700 configuration successful
    
    OB (enable) set vlan 701 type trcrf parent 700 ring 6
    
    Vlan 701 configuration successful
    
    OB (enable) set vlan 702 type trcrf parent 700 ring 7
    
    Vlan 702 configuration successful
  5. Ensure that the newly created VLANs on the Catalyst 5000 are running over the trunk.

    OB (enable) show trunk
    
    Port      Mode         Encapsulation  Status        Native vlan
    --------  -----------  -------------  ------------  -----------
    5/1       on           isl            trunking      1
    
    Port      Vlans allowed on trunk
    --------  -------------------------------------------------------------
    5/1       1-1005
    
    Port      Vlans allowed and active in management domain 
    --------  -------------------------------------------------------------
    5/1       1,480-481,700-702,804,806,902,1003,1005
  6. To support Token Ring VLANs, the Catalyst 5000 must run VTP version 2 in server mode. Issue the set vtp v2 enable command to configure this. Issue the show vtp domain command to ensure that the VTP version 2 is in server mode.

    OB (enable) show vtp domain
    
    Domain Name                      Domain Index VTP Version Local Mode  Password
    -------------------------------- ------------ ----------- ----------- --------
    ob                               1            2           server      -
    
    Vlan-count Max-vlan-storage Config Revision Notifications
    ---------- ---------------- --------------- -------------
    13         1023             26              disabled
    
    Last Updater    V2 Mode  Pruning  PruneEligible on Vlans
    --------------- -------- -------- ----------------------
    172.17.240.37   enabled  disabled 2-1000
  7. Because the Catalyst 5000 is running in VTP server mode, the Catalyst 3900 needs to run in VTP client mode. Ensure that the domain name on the Catalyst 3900 matches the domain name on the Catalyst 5000. This causes all VLANs configured on the Catalyst 5000 to be learned by the Catalyst 3900.

    trisl3_05.gif

  8. Configure port 3/16 to TrCRF 701 on the Catalyst 5000.

    OB (enable) set vlan 701 3/16
    
    VLAN  Mod/Ports
    ---- -----------------------
    701   3/16
          5/1
  9. Ensure that port 3/16 belongs to VLAN 701.

    OB (enable) show port 3/16
    
    Port  Name               Status     Vlan       Level  Duplex Speed Type
    ----- ------------------ ---------- ---------- ------ ------ ----- ---------
    3/16                     connected  701        normal  a-hdx  a-16 TokenRing
    
    Port   Trap      IfIndex
    -----  --------  -------
    3/16   disabled  358
  10. Configure port 15 on the Catalyst 3900 to belong to VLAN TrCRF 702.

    trisl3_06.gif

    trisl3_07.gif

  11. Ensure that port 15 on the Catalyst 3900 is inserted.

    trisl3_08.gif

    You need to know if the end station supports full or half duplex. If port 15 connects to a PC, then the operation mode should be PORT. If port 15 connects to a Token Ring hub, then the operation mode should be STATION. This connection can be statically configured.

    trisl3_09.gif

  12. Check the Spanning-Tree modes on the TrBRF 700 and TrCRF 701. If the BRF is configured for SRB, then it must run the IBM Spanning-Tree. If the BRF is configured for SRT, then it must run the IEEE Spanning-Tree.

    If the BRF runs the IBM Spanning-Tree, CRF can run either the IEEE or the Cisco Spanning-Tree. However, the default is the IEEE Spanning-Tree. If the BRF runs the IEEE Spanning-Tree, the CRF must run the Cisco Spanning-Tree.

    If you use default mode on the Catalyst 5000, then the IBM Spanning-Tree runs on TrBRF 700 and the IEEE Spanning-Tree mode runs on TrCRF 701. Ensure that the correct ports are forwarding.

    OB (enable) show spantree 700
    
    VLAN 700
    Spanning tree enabled
    Spanning tree type          ibm
    
    Designated Root             00-90-2b-6a-f2-bb
    Designated Root Priority    32768
    Designated Root Cost        0
    Designated Root Port        1/0
    Root Max Age   10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Bridge ID MAC ADDR          00-90-2b-6a-f2-bb
    Bridge ID Priority          32768
    Bridge Max Age 10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Port,Vlan                Vlan Port-State    Cost  Priority Portfast   Channel_id
    ------------------------ ---- ------------- ----- -------- ---------- ----------
    5/1                      700  forwarding       19        4 disabled   0
    701                      700  forwarding       62        4 disabled
    702                      700  inactive         62        4 disabled
    * = portstate set by user configuration.
    
    OB (enable) show spantree 701
    
    VLAN 701
    Spanning tree enabled
    Spanning tree type          ieee
    
    Designated Root             00-90-2b-6a-f2-bc
    Designated Root Priority    32768
    Designated Root Cost        0
    Designated Root Port        1/0
    Root Max Age   10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Bridge ID MAC ADDR          00-90-2b-6a-f2-bc
    Bridge ID Priority          32768
    Bridge Max Age 10 sec    Hello Time 2  sec   Forward Delay 4  sec
    
    Port                     Vlan Port-State    Cost  Priority Portfast   Channel_id
    ------------------------ ---- ------------- ----- -------- ---------- ----------
    3/16                     701  forwarding       62       32 disabled   0
    5/1                      701  forwarding*      19       32 disabled   0
    * = portstate set by user configuration or set by vlan 700 spanning tree.
  13. Ensure that the correct Spanning-Tree modes are running on TrBRF 700 and TrCRF 702 on the Catalyst 3900. If the traffic that is being bridged on the Catalyst 3900 is unknown, select Base on Bridging Mode. Base on Bridging Mode causes the switch to automatically select the most suitable Spanning-Tree on the TrCRF.

    trisl3_10.gif

    trisl3_11.gif

    The bridging mode for TrBRF 700 is SRB, which means that IBM Spanning-Tree runs on TrBRF 700. TrCRF 702 shows Base on the Bridging mode, which is the default Spanning-Tree for TrCRF 702. Check the Spanning-Tree information for TrBRF 700 and TrCRF 702.

    trisl3_12.gif

    trisl3_13.gif

  14. Ensure that the end station MAC addresses are learned on the correct VLAN/Port on the Catalyst 5000.

    OB (enable) show cam dynamic
    
    * = Static Entry. + = Permanent Entry. # = System Entry. R = Router Entry.
    X = Port Security Entry
    
    VLAN  Dest MAC/Route Des    [CoS]  Destination Ports or VCs / [Protocol Type] 
    ----  ------------------    -----  ------------------------------------------
    702   44:44:44:44:44:44             5/1
    1005  00:05:77:21:59:15             5/1
    701   40:00:87:87:87:87             3/16
    Total Matching CAM Entries Displayed = 3

    The Catalyst 5000 end station MAC address 4087.8787.8787 is learned on the directly attached Token Ring port 3/16. The Catalyst 3900 end station MAC address 4444.4444.4444 is learned over the TR-ISL port 5/1.

  15. Ensure that the MAC addresses have been learned on the correct VLAN/Port on the Catalyst 3900.

    trisl3_14.gif

    The Master Address Table shows that the Catalyst 3900 end station MAC address 4444.4444.4444 is learned on directly attached Token Ring port 15. The Catalyst 5000 end station MAC address 4000.8787.8787 is learned over the TR-ISL port 21.

    trisl3_15.gif

    The VLAN Address Table shows that the Catalyst 3900 end station MAC address 4444.4444.4444 is learned on directly attached Token Ring port 15. The ports on which the MAC addresses have been learned match the network topology. The TR-ISL configuration is complete.

Troubleshooting

There are many different types of TR-ISL configurations. A good way to troubleshoot them is to check the Spanning-Tree settings and the MAC address entries.

When you are troubleshooting, remember that a MAC address that is learned from the wrong port causes most problems.

Related Information

Updated: Sep 09, 2005
Document ID: 12404