The password expiry warning messages are not being received by a user when they log on.
Example of error message shown in /var/log/secure for a Linux system:
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Jul 23 17:02:12 server01 sshd[14328]: pam_vas: Authentication for user:
account: service: reason:
Kerberos error Failed to obtain credentials. Client: USER01@EXAMPLE.COM, Service: krbtgt/EXAMPLE.COM@EXAMPLE.COM, Server: server01.example.com
Caused by: UNKNOWN (1859794438): ASN.1 identifier doesn't match expected value Reason: failed to decode METHOD DATA >
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