Hi,
I have a pair of Catalyst 6500 switches and another pair of Nexus 7000 Switches. Catalyst 6500 has few set of vlans for which it's a spanning-tree root bridge and HSRP active/standby for those vlans. Nexus has few set of vlans for which it's a spanning-tree root bridge and HSRP active/standby for those vlans. Now i want to migrate all the vlans and SVI from Catalyst 6500 to Nexus 7K but the vlan numbering are same on both the Catalyst 6500 and N7K. So to avoid vlan overlapping, we decided to go with vlan translation method. So what we did was: we applied the vlan translation commands on the Catalyst 6500 switch interfaces connecting to N7K Switches. The vlan mapping looks like this:
vlan 2 will be translated to 202, 3 will be 203 and so on.
The link between the Catalyst 6500 and N7K are single sided vpc links.For all those translated vlans, now N7K is the root bridge.So i migrated the spanning-tree root functions over to the N7K but SVI's for those vlans are still in 6500 switches. Once i make the N7K as the root bridge, the problem started. What i can see is the ospf neighbor for all the SVI's are frequently changing from FULL to Down and vice-versa.Also HSRP state on Catalyst 6500 switches are transitioning to Active->Speak.
Just to give you more background. After we enable the single-sided vpc link between 6500 switches and N7K switches. the link between the 6500 switches are in blocking state so all the communication between two 6500 switches has to go thru Nexus 7000 switches.
Have anyone implemented this scenario and faced the same situation ?
