[CentOS] Testing remote machine status in a script ?

[Devin Reade]

The ping method or equivalent mechanisms (such as a test ssh into the
machine) should answer the original question.

However, in the specific context of backups, a few years ago I did for
a client an evalution of various backup solutions, including a lot of 
freeware and commercial products (including some high end and expensive
ones).  I was completely dismayed with what was available at the time
other than at the top end; products were either missing features that
I'd consider necessary for enterprise deployments, or had the features
but lacked stability.

However, about a year or two after that Bacula came out (www.bacula.org)
and I've been extreamly impressed with it.  This open source solution
is (IMO) at least as good as any of the commercial ones out there, including
the top end backup products.  It's very stable, has a fantastic feature 
set, fantastic response from the developers, and commercial support is
available for those companies wanting it.

And getting back to point, while its normal mode of operation is to back
up machines that are on the net 24/7, it can also be configured to back
up machines (like my laptop) that aren't always there.  By default an
unreachable client would be considered an error condition, but bacula can be 
set up so that it just reschedules the client for the next available
backup window.

Devin
-- 
A zygote is a gamete's way of producing more gametes.  This may be the
purpose of the universe.				- Robert Heinlein