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I have a dnsmasq service that is currently bound to 127.0.0.1 pointing to my minikube instance like so:

address=/.k8s.local/192.168.39.184

I'd like to run docker containers that will communicate with the minikube instance using the DNS I specified.
When I set the container's DNS using docker run --dns 127.0.0.1 ... docker outputs the following message: WARNING: Localhost DNS setting (--dns=127.0.0.1) may fail in containers.
If I use the the host's network like so docker run --net host --dns 127.0.0.1 ... everything works as expected.
How do I configure the docker bridge to also resolve DNS using my local dnsmasq service?

Thomas
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the_drow
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1 Answers1

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You can use the host's local DNS resolver (e.g. dnsmasq) from your Docker containers if they are on a user defined network. In that case a container's /etc/resolv.conf will have the nameserver 127.0.0.11 (a.k.a. the Docker's embedded DNS server), which can forward DNS requests to the host's loopback address properly.

$ cat /etc/resolv.conf
nameserver 127.0.0.1
$ docker run --rm alpine cat /etc/resolv.conf
nameserver 8.8.8.8
nameserver 8.8.4.4
$ docker network create demo
557079c79ddf6be7d6def935fa0c1c3c8290a0db4649c4679b84f6363e3dd9a0
$ docker run --rm --net demo alpine cat /etc/resolv.conf
nameserver 127.0.0.11
options ndots:0
Eugene Yarmash
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