Have a look on that client in /tmp/amanda, look for the files
sendsize.DATETIME.debug and see how long the estimate did take.
The first line of the file is the start time and the last line is the
finish time.  How long did it really take?  You many have to
change the "etimeout" parameter in amanda.conf.

If there is no "finish time" line, then the estimate crashed, and
probably there is an error message in that file too.

amandad: time 111.846: dgram_recv: timeout after 10 seconds
amandad: time 111.846: waiting for ack: timeout, retrying
amandad: time 121.846: dgram_recv: timeout after 10 seconds
amandad: time 121.847: waiting for ack: timeout, retrying
amandad: time 131.847: dgram_recv: timeout after 10 seconds
amandad: time 131.847: waiting for ack: timeout, retrying
amandad: time 141.847: dgram_recv: timeout after 10 seconds
amandad: time 141.848: waiting for ack: timeout, retrying
amandad: time 151.848: dgram_recv: timeout after 10 seconds
amandad: time 151.848: waiting for ack: timeout, giving up!
amandad: time 151.848: pid 17383 finish time Wed May 18 00:56:58 2005

what would cause that and i presume this could be the cause of the failure