Script for shutting down system at 9.00 PM in Centos



Please help me out with a script for shutting down system at 9.00 PM/if any system is ideal for half an hour the system should be shutdown daily in Centos. I have configured with Ldap server and having six clients systems. and I want to run through the ldap server.

  1. setup password less authentication for one user on all server

  2. grant sudo privilege (shutdown) to the user

  3. schedule cron job on ldap server to ssh -q server sudo -s /sbin/shutdown -h

my question here who bring up the server once shutdown ?