On my network 1 Mac is not showing any devices in Shared in Finder, any ideas ?

Question

A few of MacBook's, and Mac Pro's - 1 Running OS X Server.
one Mac Pro has no devices listed in Network or Shared & can't see the servers Time Machine volume, but you can connect with afp://ip_address
Any suggestions ? the 2 machines in question are wired on the same gigabit switch
Thanks in advance !

Answer 1

run the Apple Hardware Test:
To run Apple Hardware Test remotely from another computer to a MacBook Air (Original), MacBook Air (Late 2008), or MacBook Air (Mid 2009):
Make sure to install Remote Install Mac OS X on the other computer.
Insert the Mac OS X Disc into the optical disc drive of the other computer.
For Intel-based Apple computers shipping with Mac OS X v10.5.4 or earlier,AHT is located on the Mac OS X Install Disc 1 and should be included with your computer.
For Intel-based Apple computers shipping with Mac OS X v10.5.5 or later, AHT is located on the Applications Install Disc 2 and should be included with your computer.
If your other computer is a Mac, open /Applications/Utilities/Remote Install Mac OS X. On Windows, choose "Remote Install Mac OS X" from the Install Assistant.
Read the introduction and hold down the Option key while you click Continue in Remote Install Mac OS X to launch AHT.
On your MacBook Air, when the AHT chooser screen appears, select the language for your location.
Press the Return key or click the right arrow button.
When the AHT main screen appears (after about 45 seconds), follow the onscreen instructions.
If AHT detects an issue, it displays an error code. Make a note of the error code before pursuing support options. If AHT doesn’t detect a hardware issue, the issue may be software related.
On the other computer, click Quit to exit Remote Install Mac OS X. If you see a message saying the MacBook Air will be disconnected, click Quit Anyway.