01-02-2008 07:29 AM - edited 03-05-2019 08:14 PM
I have a Cisco 2960 trunked to a Foundry switch. I have configured the trunk on the Cisco as follows:
rs-b3.ott26#sh int gi0/1 switchport
Name: Gi0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none
On the Foundry, I have tagged all the VLAN's that are to be trunked over to the Cisco. However, when I do a sh span-tree I get the following output reporting that some of the VLAN's are broken. I have configured all the VLAN's the same way.
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 001a.6d4c.5180
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 001a.6d4c.5180
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/1 Desg BKN*4 128.25 P2p *PVID_Inc
VLAN0049
Spanning tree enabled protocol ieee
Root ID Priority 32817
Address 001a.6d4c.5180
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32817 (priority 32768 sys-id-ext 49)
Address 001a.6d4c.5180
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/1 Desg BKN*4 128.25 P2p *PVID_Inc
VLAN0061
Spanning tree enabled protocol ieee
Root ID Priority 32829
Address 001a.6d4c.5180
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32829 (priority 32768 sys-id-ext 61)
Address 001a.6d4c.5180
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/1 Desg BKN*4 128.25 P2p *PVID_Inc
01-03-2008 08:28 AM
Are both your devices using the same STP model, or is one doing Per Vlan STP and the other doing Mono STP? Also, are you doing regular or rapid spanning tree? Same on both devices?
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