Hello,
here comes a really weird problem we see with certain r710s (where esxi is installed) after a system bios update. when we update the system bios of one of the r710s (booting with the cdu 2.1 and after that with the suu 7.2.0), suddenly after the auto power-off-on, we lose all the network connectivity in the whole area (our testlab in this case) where the server is located for about 6 seconds.
After the 6 seconds, everything is up and running fine again. But during these seconds: No pings, no networking at all. this concerns all systems connected to the switch cascades in our testlab (many 6248s, many 8024s).
our thoughts regarding this: the r710s have two 10 gig nics and 8 1gig nics connected to 8024s (the 10 gigs) and 6248s (the 1gigs). could it be that somehow the 6248s or the 8024s see a complete takedown of a huge number of interfaces at once and thus deciding to initiate a global spanning tree topology recalculation? as the switches are configured to rstp the roundabout 6 seconds would make sense in our opinion. but this is just a first guess. Do you have any ideas or had similar experience?
Best regards
Joerg