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Local DNS resolver found in resolv.conf and containers can't use it

adamkdean profile image Adam K Dean ・1 min read

I've been playing with Docker for part of a project, and came across this annoying but important message:

WARNING: Local (127.0.0.1) DNS resolver found in resolv.conf and containers can't use it. Using default external servers : [8.8.8.8 8.8.4.4]

The problem? /etc/resolv.conf has nameserver 127.0.0.1 (or nameserver 127.0.1.1) in it.

I worked out that Ubuntu 14.04 LTS uses a daemon called dnsmasq, which routes DNS traffic through to the DNS servers provided by DHCP.

While this works fine for Docker, that message is quite annoying.

I disabled dnsmasq in /etc/NetworkManager/NetworkManager.conf:

$ sudo nano /etc/NetworkManager/NetworkManager.conf

#dns=dnsmasq

I then added the public Google DNS servers to /etc/dhcp/dhclient.conf:

$ sudo nano /etc/dhcp/dhclient.conf

prepend domain-name-servers 8.8.8.8,8.8.4.4;

Then you just need to restart NetworkManager:

$ sudo restart network-manager

And now you can start Docker containers without that pesky message!

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