DNS entries on CentOS and how to revert back

Question

I used to have opendns set up as my DNS.

network manager still has opendns IP addresses in the relevant entry of the gui. Also /etc/network/interfaces has the opendns IPs.

However, this has stopped working and I appear to be using my ISP DNS

How do I get back to my previous situation of using opendns?

Comments

How are you checking this?

Answer 1

If you don't have "managed=true" in the "[ifupdown]" section of "/etc/NetworkManager/NetworkManager.conf"?

If you don't, NM will ignore the NIC that you've defined and set up in "/etc/network/interfaces".

How are you setting the DNS servers in "/etc/network/interfaces"? The only way that you can do so (using "dns-nameservers ...") is if you have resolvconf running and "/etc/resolv.conf" is a symlink to "/run/resolvconf/resolv.conf".

(If you don't use "dns-nameservers ...", you have to use "/etc/resolvconf/resolv.conf.d/{head,base,tail}" to set the nameservers in "/etc/resolv.conf", unless you want to use those that you get via dhcp.)