What is the best way to monitor list of current leases and their states?

michael kapelko kornerr at gmail.com
Wed Jun 10 09:31:34 UTC 2009

We use DHCP with Relay Agent Info option, because we have a network of
D-Link's. We would like to see what IPs have been offered to a certain
switch port. Is that possible?
So far I came up with these possibilities:

1. dhcpd.lease
The lease file seems to be a history and doesn't seem to be a 'fast'
option for monitoring states.

In OMAPI after reading 'man omshell' I was able to examine certain IP
for its state and was presented with this unreadable reply:

> open
obj: lease
ip-address = 0a:66:64:7c
state = 00:00:00:02
dhcp-client-identifier = 01:00:0e:a6:56:56:07
client-hostname = "computer-455d96"
subnet = 00:00:00:02
pool = 00:00:00:03
hardware-address = 00:0e:a6:56:56:07
hardware-type = 00:00:00:01
ends = 2a:7a:2f:4a:00:00:00:00
starts = 24:78:2f:4a:00:00:00:00
tstp = 00:00:00:00:00:00:00:00
tsfp = 72:7a:2f:4a:00:00:00:00
cltt = 24:78:2f:4a:00:00:00:00

which is even harder to understand than dhcpd.lease. Any help on what
these values are or where I can read about them? 'man omshell' only
says, 'Any data  that  isn't readily  printable  text will show up in
colon-separated hexadecimal values'.

3. syslog
Well, this looks most stupid and probably is.

What is the best to accomplish the monitoring?

More information about the dhcp-users mailing list