i got the same problem, my interfaces looks like
iface lo inet loopback
iface eth0 inet static address 192.168.1.1 netmask 255.255.255.0 gateway 192.168.1.100
i got a second configuration in my network-manager, after skipping to e.g. 192.168.1.3. network comes up but after reboot i have to change IP again.
i got the same problem, my interfaces looks like
iface lo inet loopback
iface eth0 inet static
address 192.168.1.1
netmask 255.255.255.0
gateway 192.168.1.100
i got a second configuration in my network-manager, after skipping to e.g. 192.168.1.3. network comes up but after reboot i have to change IP again.