LLDP-MED advertises the voice VLAN, but the access switch data policy overrides it after a bounce
Phones boot into the right segment once, then move unexpectedly because another edge policy reclassifies the port after link renegotiation.
NetworkIntermediate
IPv6 ND inspection keeps a stale binding after renumbering, and hosts with new addresses cannot pass traffic on the access edge
Security stays enabled, but address lifecycle assumptions lag behind the renumbered endpoint state.
NetworkIntermediate
One switch in the ring has the wrong MST region name, and the topology becomes a boundary only after a reboot reloads the saved config
The live network was temporarily aligned, but the persisted spanning-tree identity says otherwise.
NetworkIntermediate
An STP root move succeeds while BPDU guard from an access template errdisables the recovery uplink during a failover rehearsal
The topology change is valid and an inherited safeguard still treats it as hostile. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.