Phew, that was a scary one....

[icecream-guy]

throw one more log in the fire,  if you read the Cisco Nexus vlan configuration guide in detail (we didn't here and got bit by this one)

Nexus supports the standard range VLAN's 1 - 4094.

VLAN 2- 1005 can be created, modified, used, and deleted

VLANs 1006 - 4094 can be created, modified, used, and deleted, you cannot change the state, state is always active, VLAN is always enabled, cannot shut down.

So what happens when one of your 5k (also seen this on 9K's) are upgraded, or one switch fails.
When the VPC fails, all your VLAN's 2-1005 will go into suspended state, thus shutting all the VLAN's down on your surviving switch.

Cisco recommends forcing your VLANs 2-1005 to active state so they never shut down, and will not go into a suspended state during a failure.

Code Select Expand


vlan 55
name networking-forums
state active
no shutdown


[NetworkGroover]

throw one more log in the fire,  if you read the Cisco Nexus vlan configuration guide in detail (we didn't here and got bit by this one)

Nexus supports the standard range VLAN's 1 - 4094.

VLAN 2- 1005 can be created, modified, used, and deleted

VLANs 1006 - 4094 can be created, modified, used, and deleted, you cannot change the state, state is always active, VLAN is always enabled, cannot shut down.

So what happens when one of your 5k (also seen this on 9K's) are upgraded, or one switch fails.
When the VPC fails, all your VLAN's 2-1005 will go into suspended state, thus shutting all the VLAN's down on your surviving switch.

Cisco recommends forcing your VLANs 2-1005 to active state so they never shut down, and will not go into a suspended state during a failure.

Code Select Expand


vlan 55
name networking-forums
state active
no shutdown


Lol, I always try to push our software/dev team to force stuff like this if it's a "always" situation.  If it's a "always" situation, we shouldn't force operators to have to know about/remember/configure it.  No point.

[icecream-guy]

Had to fix that, left the 's' off my VLAN name.

[LynK]

Even the newer 10G modules have the buffer issues?

We were looking at:

N2K-C2348UPQ
N2K-C2332TQ

[icecream-guy]

Even the newer 10G modules have the buffer issues?

We were looking at:

N2K-C2348UPQ
N2K-C2332TQ

I think the 2300 series does away with that,  it also moves some of the processing to the FEX itself.