whm Could not open /etc/resolv.conf: Permission denied
CentOS 7.5 - name server entry in resolv.conf
resolv.config readonly

centos 7


Just change permissions temporarily:

sudo chmod 744 /etc/resolv.conf
Add nameservers of your VPN provider by editing the file with text editor:

nameserver ip_of_nameserver_one
nameserver ip_of_nameserver_two
Save the file,then revert permissions.
sudo chmod 644 /etc/resolv.conf
sudo chattr +i /etc/resolv.conf
The last command will add immutable bit, so the file doesn't get overwritten. After you set immutable bit, even the root account will not be able to write to the file. If you wish to edit the file again latter on, and remove immutable bit, use this command:
sudo chattr -i /etc/resolv.conf