ip http secure-session hard-timeout

This command configures the hard timeout for secure HTTP sessions in hours. When this timeout expires, the user is forced to reauthenticate. This timer begins on initiation of the web session and is unaffected by the activity level of the connection. The secure-session hard-timeout cannot be set to zero (infinite).

Default 24
Format ip http secure-session hard-timeout 1-168
Mode Privileged EXEC