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New Member

vss dual-active crash

HI everyone 
   our two 6509 configured VSS , standby box SUP crashed at mid night and not 
came back online itself,remain in ROMMON.
   we found at same time , one upstream switch  has two interfaces
connect to this two box seperatly, this two interfaces were down at same time.
   all communication through VSS had been down for almost 8 hours until we found 
problem on morning  and reboot standby box, now it is ok
   but in this failure, standby box crashed , active box lost vsl and dual-detect
link , this was not dual-active , why upstream switch two interfaces were all down.
   I think during standby box sup crashed. in this short moment,TWO BOXES WERE NOT STABLE
, active box DUAL-DETECT MECHANISM had some LITTLE opportunity or  time to detect dual-active, and shutdown it's interface.and
BUT unforturnately standby box hadn't come back and remained in ROMMON. so upstream switch two interfaces were all down

   if I am correct, this is ridiculous, because i can't avoid this kind of standby box sup crash failure .
does one active box in VSS don't has ability to come back from this failure automatically.
how can I config to made old-active box interface come back if standby box go into ROMMON status for a long time.
 THANK you!

Everyone's tags (1)
New Member

Looks like your Upstream

Looks like your Upstream switch MEC (port channel) was not configured properly or for some reason, STP kicked in, even thought with VSS STP should be automatically disabled.

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