VSS VSL cables unplugging steps to avoid status change

[indraadi82]

Hi All,

I have a VSS with 2 4500-X. Currently there are 2 VSL ports and 1 DAD (Dual Active Detection) port. 

And now I'm planning to do a cabling tidy up with those 3 port cables involved. I want to avoid any 

restart on my active 4500-X due to VSS behavior (if happens). So, are these steps correct:

1. Unplug 1 VSL cable, tidy up & plug it back in

2. Unplug 1 VSL cable, tidy up & plug it back in

3. Unplug 1 DAD cable, tidy up & plug it back in 

Can these steps avoid VSS active switch from restarting and also avoid changing its status from active to standby? I already decided which switch is the active one. Therefore, I don't expect 

it to change after doing the cable tidy up.

Thanks! 

[Rolf Fischer · Accepted solution]

Hi,

as long as at least one VSL is operational, there will be no VSS status change.

However, to be on the safe side, you could temporarily add one or more additional VSLs (up to 8 are supported) before you remove the ones you want to tidy up.

When you remove the fast hello link, you just loose the mechanism to detect a dual active condition provided by this link. Although there is no risk of a status change here, you could configure more than one fast hello link as well.

HTH

Rolf

[Leo Laohoo]

Power down the secondary otherwise there's going to be a potential "split brain" scenario.