We have a server that recently has been displaying strange behavior. Every day at 8:00am and 4:00p the server will "crash". Messages on the console screen indicate that the sys volume was dismounted. The client machines get the same message in a pop-up. The server console is up and responsive. Nothing is written to the abend.log or logger screen as to why it dismounted sys. Just states that it did. After this happens those who are logged in stay logged in although they can access nothing on that server. Those who are trying to login receive a message that the tree or server cannot be found. The odd part about this is that the server does this at regular intervals.
Thanks in advance for any assistance you can provide.