Symptom
We can see the following error messages displayed in syslogs:
Jul 18 2023 10:57:01.286 PDT: %SEC_LOGIN-1-QUIET_MODE_ON: Still timeleft for watching failures is 0 secs, [user: ] [Source: 192.168.1.5] [localport: 23] [Reason: Login Authentication Failed] [ACL: sl_def_acl] at 10:57:01 PDT Tue Jul 18 2023
Jul 18 2023 10:57:08.879 PDT: %SEC_LOGIN-4-LOGIN_FAILED: Login failed [user: ] [Source: 192.168.1.5] [localport: 23] [Reason: Login Authentication Failed] at 10:57:08 PDT Tue Jul 18 2023
TCP sessions fail to establish
SW1_#sh ip ports all
Proto Local Address Foreign Address State PID/Program Name
TCB Local Address Foreign Address (state)
tcp 192.168.1.6:23 192.168.1.5:48788 TIMEWAIT 0/[IOS] Unknown
Conditions
- 2 9300 switches in stack
-The Cisco IOS Login Enhancements (Login Block) feature
Workaround
Remove The Cisco IOS Login Enhancements (Login Block) feature
Further Problem Description
All remote access is blocked and switch becomes unaccesible
