We have two SG550XG324T stacked together (Firmware ver 2.5.0.90) and setup LAG (No enable LACP) say 1/5 and 2/5 connected to Xen server (Bond mode Active-Active No LACP)
Issue
Both port always up and down and one of port (1/5) automatic from active member to standby member, do you have see this issue?
Tried
Exchange the switch
Upgrade the switch firmware
Change all patch cable
Upgrade the Xen server patch
Change switch and Xen server form LACP to no LACP