Argthtjtr

In my docker-compose.yml file, I have the following. However the container does not pick up the hostname value. Any ideas?

dns:

  image: phensley/docker-dns

  hostname: affy

  domainname: affy.com

  volumes:

    - /var/run/docker.sock:/docker.sock

I found that the hostname was not visible to other containers when using docker run. This turns out to be a known issue (perhaps more a known feature), with part of the discussion being:

We should probably add a warning to the docs about using hostname. I think it is rarely useful.

The correct way of assigning a hostname - in terms of container networking - is to define an alias like so:

services:

  some-service:

    networks:

      some-network:

        aliases:

          - alias1

          - alias2

Unfortunately this still doesn't work with docker run. The workaround is to assign the container a name:

docker-compose run --name alias1 some-service

And alias1 can then be pinged from the other containers.

This seems to work correctly. If I put your config into a file:

$ cat > compose.yml <<EOF

dns:

  image: phensley/docker-dns

  hostname: affy

  domainname: affy.com

  volumes:

    - /var/run/docker.sock:/docker.sock

EOF

And then bring things up:

$ docker-compose -f compose.yml up

Creating tmp_dns_1...

Attaching to tmp_dns_1

dns_1 | 2015-04-28T17:47:45.423387 [dockerdns] table.add tmp_dns_1.docker -> 172.17.0.5

And then check the hostname inside the container, everything seems to be fine:

$ docker exec -it stack_dns_1 hostname

affy.affy.com

Based on docker documentation:
https://docs.docker.com/compose/compose-file/#/command

I simply put
hostname: <string>
in my docker-compose file.

E.g.:

[...]



lb01:

  hostname: at-lb01

  image: at-client-base:v1



[...]

and container lb01 picks up at-lb01 as hostname.

I needed to spin freeipa container to have a working kdc and had to give it a hostname otherwise it wouldn't run.
What eventually did work for me is setting the HOSTNAME env variable in compose:

version: 2

services:

  freeipa:

    environment:

      - HOSTNAME=ipa.example.test

Now its working:

docker exec -it freeipa_freeipa_1 hostname

ipa.example.test