Discovery of a computer on the network

[vwgtiturbo]

I am still working on remodeling a backup shell script. It already works, but I can't leave it alone...
Right now, I have the script set to wake up my remote server using ether-wake, then sleep for abour 3 minutes so the system can boot and get ready for some rsync transfers. Well, the boot time isn't consistent, it's just an estimate. So, instead of my hard-coding 'sleep 180', I am trying to figure out a way to better 'probe' to see if the computer is booted and ready or not.
I could only think of two options:
1) Ping the server's address, then somehow grep the results for replies, and output those results to a file. Use a if/then loop to see if the file exists. If so, continue with the program. If not, wait a few seconds. In theory, if the server wasn't awake yet, no replies would be received, therefore, the file shouldn't exist, and my system should wait a few seconds.
2) Write a simple boot script to use scp to copy some data/file to my client machine. Once again, use an if/then to see if the file exists. If so, continue, if not, wait a few.

I know that these probably aren't ideal as I haven't been around too much, so I was wondering if someone has a better suggestion?

[Schotty]

That may not be the best idea, a sleep 3 minutes may be a better idea, since the services may not start in the order that you would prefer if just ... pinging or so.

Perhaps have the server when up, talk to the backup server to start the backup

server ssh's to backupserver and runs command to suck data down from server to backupserver.

its an idea

[vwgtiturbo]

That makes sense, as far as the services starting... I may look into the 'sucking' idea. It wouldn't take much rework in my script, besides copying it to the backup server from my local machine...