ltsp not loading on boot

[dbclinton]

Hi,
Two or three times over the past few weeks I've booted my LTSP server 
(Edubuntu 12.04) but was unable to boot any clients - there were simply 
no signs of life over the network from the server (which itself was 
running happily). Rebooting each time solved the problem, but I'd like 
to know what's actually going wrong.
Running
/var/log$ cat syslog.1 | grep ltsp
on the entries from an unsuccessful session differed from a successful 
boot only in that each hostkey was created once, rather than three times.

Here's the unsuccessful session:

Jan  5 17:50:12 dbclinton ltsp: # Creating dsa-hostkey for dbclinton
Jan  5 17:50:12 dbclinton ltsp: # Creating rsa-hostkey for dbclinton
Jan  5 17:50:12 dbclinton ltsp: # Creating ecdsa-hostkey for dbclinton
Jan  5 17:50:12 dbclinton ltsp: # Creating dsa-hostkey for 192.168.0.254
Jan  5 17:50:12 dbclinton ltsp: # Creating rsa-hostkey for 192.168.0.254
Jan  5 17:50:12 dbclinton ltsp: # Creating ecdsa-hostkey for 192.168.0.254
Jan  5 17:50:12 dbclinton ltsp: # Creating dsa-hostkey for 10.0.0.2
Jan  5 17:50:12 dbclinton ltsp: # Creating rsa-hostkey for 10.0.0.2
Jan  5 17:50:12 dbclinton ltsp: # Creating ecdsa-hostkey for 10.0.0.2
Jan  5 17:50:12 dbclinton ltsp: # Creating dsa-hostkey for 10.0.3.1
Jan  5 17:50:12 dbclinton ltsp: # Creating rsa-hostkey for 10.0.3.1
Jan  5 17:50:12 dbclinton ltsp: # Creating ecdsa-hostkey for 10.0.3.1

And here's the same search from a successful session:

Jan  5 18:30:39 dbclinton ltsp: # Creating dsa-hostkey for dbclinton
Jan  5 18:30:39 dbclinton ltsp: # Creating rsa-hostkey for dbclinton
Jan  5 18:30:39 dbclinton ltsp: # Creating ecdsa-hostkey for dbclinton
Jan  5 18:30:39 dbclinton ltsp: # Creating dsa-hostkey for 10.0.0.2
Jan  5 18:30:39 dbclinton ltsp: # Creating rsa-hostkey for 10.0.0.2
Jan  5 18:30:39 dbclinton ltsp: # Creating ecdsa-hostkey for 10.0.0.2
Jan  5 18:30:39 dbclinton ltsp: # Creating dsa-hostkey for 192.168.0.254
Jan  5 18:30:39 dbclinton ltsp: # Creating rsa-hostkey for 192.168.0.254
Jan  5 18:30:39 dbclinton ltsp: # Creating ecdsa-hostkey for 192.168.0.254
Jan  5 18:30:39 dbclinton ltsp: # Creating dsa-hostkey for 10.0.3.1
Jan  5 18:30:39 dbclinton ltsp: # Creating rsa-hostkey for 10.0.3.1
Jan  5 18:30:39 dbclinton ltsp: # Creating ecdsa-hostkey for 10.0.3.1
Jan  5 18:32:00 dbclinton ltsp: # Creating dsa-hostkey for dbclinton
Jan  5 18:32:00 dbclinton ltsp: # Creating rsa-hostkey for dbclinton
Jan  5 18:32:00 dbclinton ltsp: # Creating ecdsa-hostkey for dbclinton
Jan  5 18:32:00 dbclinton ltsp: # Creating dsa-hostkey for 192.168.0.254
Jan  5 18:32:00 dbclinton ltsp: # Creating rsa-hostkey for 192.168.0.254
Jan  5 18:32:00 dbclinton ltsp: # Creating ecdsa-hostkey for 192.168.0.254
Jan  5 18:32:03 dbclinton ltsp: # Creating dsa-hostkey for dbclinton
Jan  5 18:32:03 dbclinton ltsp: # Creating rsa-hostkey for dbclinton
Jan  5 18:32:03 dbclinton ltsp: # Creating ecdsa-hostkey for dbclinton
Jan  5 18:32:03 dbclinton ltsp: # Creating dsa-hostkey for 192.168.0.254
Jan  5 18:32:03 dbclinton ltsp: # Creating rsa-hostkey for 192.168.0.254
Jan  5 18:32:03 dbclinton ltsp: # Creating ecdsa-hostkey for 192.168.0.254
Jan  5 18:32:03 dbclinton ltsp: # Creating dsa-hostkey for 10.0.0.2
Jan  5 18:32:03 dbclinton ltsp: # Creating rsa-hostkey for 10.0.0.2
Jan  5 18:32:03 dbclinton ltsp: # Creating ecdsa-hostkey for 10.0.0.2
Jan  5 18:32:03 dbclinton ltsp: # Creating dsa-hostkey for 10.0.3.1
Jan  5 18:32:03 dbclinton ltsp: # Creating rsa-hostkey for 10.0.3.1
Jan  5 18:32:03 dbclinton ltsp: # Creating ecdsa-hostkey for 10.0.3.1

====================

Is there anything else I should be looking at?
Thanks,
David Clinton