DNS settings wiped out after reboot

Support & Help Requests
#1

Hi,
I am trying to install ubuntu mate on an older computer in the office of my apartment complex for residents to use. The only stipulation is that it must use a content filter to block adult content. I have tried repeatedly to setup OpenDNS’s Family Shield DNS, but on reboot the settings are gone. I am using the GUI network manager. Can anyone help?

#2

does the pc get a static or dynamic ip? if static, you can set dns in /etc/network/interfaces

auto eth0
iface eth0 inet static
    address 192.168.2.101
    netmask 255.255.255.0
    gateway 192.168.2.1
    dns-nameservers  1.1.1.1 8.8.8.8
#3

Currently is DHCP but I guess I could setup static ip.