ip address on lan getting hijacked

[chris dunn]

My home lan is set up based upon a Linksys wireless access point and router 
which has an address of 192.168.1.1. My main work station is set with a 
static ip address of 192.168.1.2, (in /etc/network/interfaces) and I use 
other work stations to access this machine via nxclient and nxserver (running 
on 192.168.1.2).

All works well until 9.30 a.m. every morning when 192.168.1.2 is taken down 
and reset to 192.168.1.100, apparently by dhclient accessing the dhcp server 
running on the wap. Any nxclient connections crash as the nxserver ip address 
has changed.

Syslog provides the following messages :

May 30 09:30:04 bessie dhclient: DHCPREQUEST of <null address> on eth0 to 
255.255.255.255 port 67
May 30 09:30:33 bessie last message repeated 2 times
May 30 09:31:18 bessie last message repeated 3 times
May 30 09:31:31 bessie avahi-daemon[5615]: Withdrawing address record for 
192.168.1.2 on eth0.
May 30 09:31:31 bessie avahi-daemon[5615]: Leaving mDNS multicast group on 
interface eth0.IPv4 with address 192.168.1.2.
May 30 09:31:31 bessie avahi-daemon[5615]: Interface eth0.IPv4 no longer 
relevant for mDNS.
May 30 09:31:31 bessie avahi-autoipd(eth0)[28025]: Found user 'avahi-autoipd' 
(UID 104) and group 'avahi-autoipd' (GID 112).
May 30 09:31:31 bessie avahi-autoipd(eth0)[28025]: Successfully called 
chroot().
May 30 09:31:31 bessie avahi-autoipd(eth0)[28025]: Successfully dropped root 
privileges.
May 30 09:31:31 bessie avahi-autoipd(eth0)[28025]: Starting with address 
169.254.7.23
May 30 09:31:36 bessie avahi-autoipd(eth0)[28025]: Callout BIND, address 
169.254.7.23 on interface eth0
May 30 09:31:36 bessie avahi-daemon[5615]: Joining mDNS multicast group on 
interface eth0.IPv4 with address 169.254.7.23.
May 30 09:31:36 bessie avahi-daemon[5615]: New relevant interface eth0.IPv4 
for mDNS.
May 30 09:31:36 bessie avahi-daemon[5615]: Registering new address record for 
169.254.7.23 on eth0.IPv4.
May 30 09:31:40 bessie avahi-autoipd(eth0)[28025]: Successfully claimed IP 
address 169.254.7.23
May 30 09:31:40 bessie avahi-autoipd(eth0)[28025]: Got SIGTERM, quitting.
May 30 09:31:40 bessie avahi-autoipd(eth0)[28025]: Callout STOP, address 
169.254.7.23 on interface eth0
May 30 09:31:40 bessie avahi-daemon[5615]: Withdrawing address record for 
169.254.7.23 on eth0.
May 30 09:31:40 bessie avahi-daemon[5615]: Leaving mDNS multicast group on 
interface eth0.IPv4 with address 169.254.7.23.
May 30 09:31:40 bessie avahi-daemon[5615]: Interface eth0.IPv4 no longer 
relevant for mDNS.
May 30 09:31:40 bessie avahi-autoipd(eth0)[28026]: client: RTNETLINK answers: 
No such process
May 30 09:31:41 bessie dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 
67 interval 4
May 30 09:31:42 bessie dhclient: DHCPOFFER of 192.168.1.100 from 192.168.1.1
May 30 09:31:42 bessie dhclient: DHCPREQUEST of 192.168.1.100 on eth0 to 
255.255.255.255 port 67
May 30 09:31:42 bessie dhclient: DHCPACK of 192.168.1.100 from 192.168.1.1
May 30 09:31:42 bessie avahi-daemon[5615]: Joining mDNS multicast group on 
interface eth0.IPv4 with address 192.168.1.100.
May 30 09:31:42 bessie avahi-daemon[5615]: New relevant interface eth0.IPv4 
for mDNS.
May 30 09:31:42 bessie avahi-daemon[5615]: Registering new address record for 
192.168.1.100 on eth0.IPv4.
May 30 09:31:42 bessie dhclient: bound to 192.168.1.100 -- renewal in 35646 
seconds.
May 30 09:32:45 bessie ntpd[30757]: Listening on interface #8 eth0, 
192.168.1.100#123 Enabled
May 30 09:32:45 bessie ntpd[30757]: Deleting interface #5 eth0, 
192.168.1.2#123, interface stats: received=205, sent=205, dropped=0, 
active_time=85501 secs

All I can deduce from this is that dhclient and avahi, apparently working 
together, are combining to ruin my local network experience, and to reset the 
ip address. Understood that I don't need to run dhclient since I'm using 
static addresses, but I'm not sure how to turn it off.

What really puzzles me though is why this happens at 9.30 a.m. every day, and 
not at any other time, and how avahi gets involved in the process.

Any clues as to what is taking place, and how to switch off dhclient would be 
exceedingly welcome.

Tia.

-- 
Chris Dunn

The facts, although interesting, are irrelevant.