Automatic shutdown of NFSRooted machines?

Question

I've got a server and several client computers onsite. The client computers PXEBoot and get their / via NFS from the server. The server and clients are on limited battery backup, but the power goes out with some frequency due to factors beyond my control at this time. My problem is that when the power goes out, the server shuts down politely but the client machines do not.

I'm wondering, is there an existing elegant solution to getting the clients to shutdown before, or even just at the same time as the server? The clients only take seconds to shutdown, they can easily complete shutdown before the server does.

PS. Downtime isn't as big of a concern as a clean shutdown for these computers.

Answer 1

Assuming it's an APC UPS, there's support in APCUPSD for a client to query a server about its UPS status.

If not, then you could have the clients poll a server folder every X seconds, and if a particular file showed up in the folder, to start a clean shutdown. Have the server's normal shutdown procedures create that file, then sleep for 2X seconds. Make sure the server's normal startup procedures remove that file.