Determining availability of a remote machine

[Michael Still]

Hey,

I need to be able to determine if a remote machine is available without
living through a long timeout. For network configuration reasons I can't
use ICMP.

Anyone have a brilliant idea as to how to determine if a machine is alive
in code without using ICMP? I thought of just connecting to a port, but I
can't gaurantee that certain ports are open on the remote side, and
firewalls might get in my way.

Thanks,
Mikal

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Michael Still (mikal at stillhq.com) | Stage 1: Steal underpants
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