[c-nsp] *** GMX Spamverdacht *** Re: Weird problem with 2960S and desktop switch

[Alan Buxey]

You've turned off protection and control. ... which means that the downstream switch had the chance to mess you up.  Especially as your switch is in flat mode and thus very susceptible for vlan 1 to be messed up. ... which I'm guessing you use for management.  
The downstream switch might be taking over root Bridge mode for vlan 1, it might have a nasty l2 loop on it etc etc.
Only turn off protection on links to kit you can really really Trust... and prepare to get messed up by links that have such protection turned off in the future at some time (and change config on this switch to use a different vlan for edge/end devices)

Alan
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