My Dell precision M4800, running Ubuntu 14.04 LTS, periodically changes its IP address. It looks like the DHCP lease expires and for some reason it gets a new IP adress instead of renewing the old lease.
Possibly relevant output from syslog:
Jan 25 12:14:19 pc-1838 NetworkManager[1360]: <info> (eth0): DHCPv4 state changed reboot -> expire
Jan 25 12:14:14 pc-1838 dhclient: message repeated 781 times: [ DHCPREQUEST of 192.168.1.63 on eth0 to 255.255.255.255 port 67 (xid=0x79a31c7e)]
Jan 25 12:14:19 pc-1838 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 3 (xid=0x648ffe4b)
Jan 25 12:14:19 pc-1838 NetworkManager[1360]: <info> (eth0): DHCPv4 state changed expire -> preinit
Jan 25 12:14:22 pc-1838 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6 (xid=0x648ffe4b)
Jan 25 12:14:28 pc-1838 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 12 (xid=0x648ffe4b)
Jan 25 12:14:40 pc-1838 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14 (xid=0x648ffe4b)
Jan 25 12:14:54 pc-1838 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11 (xid=0x648ffe4b)
Jan 25 12:14:57 pc-1838 dhclient: DHCPREQUEST of 192.168.1.71 on eth0 to 255.255.255.255 port 67 (xid=0x4bfe8f64)
Jan 25 12:14:57 pc-1838 dhclient: DHCPOFFER of 192.168.1.71 from 192.168.1.1
Jan 25 12:14:57 pc-1838 dhclient: DHCPACK of 192.168.1.71 from 192.168.1.1
Jan 25 12:14:57 pc-1838 dhclient: bound to 192.168.1.71 -- renewal in 35252 seconds.
Searches with google, here, and elsewhere have been fruitless.
This behavior is annoying because I often have long-running ssh connections to this machine that of course break with no warning when the IP changes.
Maybe its a misconfiguration with dhclient or Network Manager? But what's the setting? (And why would there even be a setting for this? Who would want this behavior?)
FWIW, this never happens to my other Linux box (which runs Sabayon). So it seems like I should be able to get my Ubuntu box to stop this.
ip addr