So I have been recently playing with the recent rc’s of docker (1.12-rc2/rc3) and am experiencing some unexpected results.
Initially I created 3 ubuntu vm’s using vagrant (I installed the latest docker rc’s using the script at test.docker.com).
Deploying my stack worked, however dns resolution only worked if a service was running on the same node as the service calling it (verified by connecting to a running container and running nslookup for services on the same and different nodes).
I tried using the default overlay network and creating a new one, with the same result.
This morning I ditched the ubuntu vm’s and created three new vm’s using docker-machine with the boot2docker image. Dns resolution now works as expected.
Apart from the host image, all steps are the same. Am I missing something??