I'm attempting to setup a network of three computers and some peripheral devices using an Ethernet switch and static IP addresses. All of the computers are using Ubuntu 14.04 LTS. On two of the three computers, everything works fine, but on the third I encounter a problem.
ifconfig eth0 192.168.9.3, I set a static IP address. By typing
ifconfig, I can verify that the IP address is setup, and pinging the address from another computer works. However, after a short amount of time (<20s), using
ifconfig shows that the IP address that I had set earlier is no longer associated with eth0 -- it has disappeared!
I then altered the network interfaces file to establish the exact network made using
ifconfig in an attempt to make the setup permanent; this didn't work either, and the setup was ignored or reset. What would cause this behavior?
Likely this problem is very basic, but I have been struggling with it for some time, and any pointers or advice would be appreciated.
Update: I tried reverting all of the files back to their original states. I also poked around with the network manager, and tried setting the IP addresses with that, which worked. It seems that there is some sort of conflict between the different tools used to setup networks graphically versus in the command line, but I still don't understand why, so my original question still stands!