question about DHCPACK log entries

[Kirsten Petersen]

I have a script that parses our dhcp logs to generate a happy little table 
of mac->ip addresses mappings for a particular subnet.  Because I only 
care about the one subnet, I was doing a regular expression match on the 
gateway IP.  But then I noticed that the format of the DHCPACK log entries 
isn't always the same - and sometimes doesn't include the gateway address. 
Examples follow.  Can someone shed a little light on what is happening 
here?  We are running 3.0.4, fyi.

Log entries in question:

Mar  1 12:45:48 ns1 dhcpd: DHCPACK on 128.193.143.180 to 00:16:6f:67:89:e6 
via 128.193.136.1
Mar  1 12:45:48 ns2 dhcpd: DHCPACK on 128.193.143.180 to 00:16:6f:67:89:e6 
via 128.193.136.1
Mar  1 13:11:02 ns1 dhcpd: DHCPACK on 128.193.143.180 to 00:16:6f:67:89:e6 
via eth0
Mar  1 13:11:11 ns1 dhcpd: DHCPACK on 128.193.143.180 to 00:16:6f:67:89:e6 
via eth0

Notice that at 12:45, the ACK log entry includes the gateway address, but 
at 13:11, it does not.  Why is that?

Thanks in advance.

________________
Kirsten Petersen
Network Services * Oregon State University
http://oregonstate.edu/net * irc.oregonstate.edu #osu-is
"If you're not learning, you're not living."