Symptom
C9400 running 16.6.3 or below
When PoE interface comes up with specific config, that causes high CPU (even one port can cause 100% CPU) and if that state stays for longer time, it eventually leads to crash in IOMd, followed by IOSd.
!
During crash in IOMd, line card(s) will stop working. Even a physical re-seat of line card wont help to bring up interfaces, a complete reload of switch is needed to recover.
switch# sh platform software iomd 5/0 oir
IOMD (Input Output Module Driver) Status
PSM
PSM state: wait_start <<<< should be Ready, ideally.
HA state: not ready
Start bringup: No
Wait start timeout: 0
Hardware OK timeout:
Initialization timeout: 360000
Remove hold timeout: 5000
Remove timeout: 120000
Flags: 0000000000
SPA
Inserted spa type: unknown
Active spa type: unknown
Plugin spa type:
Power: On
Present: Yes
Reloads: 0
Ok: Yes
!
switch# sh hw-module subslot 5/0 ?
% The indicated slot/subslot number is empty . <<< It shows this o/p even though module is present, at broken state.
Conditions
Applicable to all 3k and 9k platforms running 16.6.3 or below
Following configuration
Interface GigabitEthernet1/0/13
switchport access vlan 10
switchport mode access
switchport port-security maximum 4
switchport port-security violation restrict
switchport port-security aging time 2
switchport port-security aging type inactivity
switchport port-security load-interval 60
authentication event fail action next-method
authentication event server dead action authorize vlan 10
authentication event server dead action authorize voice <<<<<<< without any voice Vlan configuration on port
!
Workaround
Either add "switchport voice vlan " under port OR remove "authentication event server dead action authorize voice", to avoid running into this issue.
