Please provide a way to overwrite the nameserver

[slankes]

Hi,

the image has the google nameservers hardwired which in turn means that dns base blacklists don't work or are blocked.

I've "fixed" this now by overriding /etc/resolv.conf but maybe there could be a more general solution (maybe using /config/resolv.conf if it exists?).

[tiredofit]

Docker defaults to using googles DNS if you haven't made a custom declaration in your dockerd startup options. Have a look at the docker --dns argument. Also, this works on docker-compose using the dns: declaration.

Running anything involving an MTA is a good idea to use a caching nameserver like Unbound. I have an image available tiredofit/unbound that should work without any setting of environment variables`. You'll just need to assign it a static IP inside a docker network, or expose port 53 to your internal network and you'll stop hammering the public DNS servers when mail comes in.

^^ Unfortunately I've made a lot of changes to some images in past few weeks and just realized I have not updated documentation for that unbound image. All of the environment variables have changed, so, either use it with no settings (they are sane defaults) or wait a few days till I can get it up to date, or use another one.