Which log file should the BIG-IP Administrator check to determine if aspecific user tried to...

Comprehensive and Detailed Explanation From BIG-IP Administration Control Plane Administration documents:

On BIG-IP systems,all authentication attemptsfor administrative access—including logins to theConfiguration Utility (GUI)—are logged in/var/log/secure. This log file records:

Successful and failed login attempts

The username used

The authentication method (local, LDAP, RADIUS, etc.)

Access denials and PAM authentication errors

Why the other options are incorrect:

/var/log/pam/tallylogtracks account lockouts and failed attempt counters, not detailed login attempts.

/var/log/ltmlogs traffic management events, not administrative authentication.

/var/log/httpdlogs web server activity but does not record authentication success or failure for BIG-IP administrative users.

Therefore, the correct log file to verify whether a user attempted to log in to the BIG-IP Configuration Utility is/var/log/secure.

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