nologin - file to restrict logins to a system
/etc/nologin
If the /etc/nologin file exists, it restricts logins to a system. After displaying the contents of the nologin file, the login procedure terminates, preventing the user from logging onto the machine.
This procedure is preferable to terminating a user's session by shutdown shortly after the user has logged on.
Logins by the following users are not affected by this procedure:
Super-user
Users assigned the root role
Users assigned the solaris.system.maintenance authorization
The message contained in the nologin file is editable by a super-user or a user with the “Maintenance and Repair” rbac(7) profile. A typical nologin file contains a message similar to:
NO LOGINS: System going down in 10 minutes.
The nologin file may be manually created by a system administrator when doing maintenance, or it may be automatically created, such as by the shutdown(8) command, by init(8) when transitioning to single user mode, or by the system when recovering a deferred dump.
The svc:/system/rmtmpfiles service will remove any existing nologin file during system boot.
login(1), pam_acct_mgmt(3PAM), pam_sm_acct_mgmt(3PAM), pam_unix_account(7), init(8), shutdown(8)
Support for /etc/nologin was present in SunOS 4.x releases, but not in Solaris 2.x releases until it was added in Solaris 2.5.