I have some containers that have a frontend and backend network defined. Currently, if I perform a name resolution on those containers I am receiving both addresses.

We should consider a config.json option that excludes specifically labeled OR named networks from being advertised over DNS.

For arguments sake, we'll consider the containers db, redis, and app as created by the following docker-compose file:

networks:
  frontend
  backend:
    internal: true

services:
  db:
    image: mariadb
    networks:
      - backend
  redis:
    image: redis
    networks:
     - backend
  app:
    image: my_custom_app
    networks:
      - backend
      - frontend
    depends_on:
      - db
      - redis

If we dig <rawdns_container> app.tld then I should only receive the frontend IP address.

We can achieve this through some configuration option like:

{
	"docker.lab.local." {
		"type": "containers",
		"exclude": {
			"labels": [ "DO_NOT_RESOLVE" ]
			"names": [ "backend" ]
		}
		"socket": "unix:////var/run/docker.sock"
	},
	"lab.local.": {
		"type": "forwarding",
		"nameservers": [ "192.168.1.250" ]
	}
	".": {
			"type": "forwarding",
			"nameservers": [ "208.67.220.220" ]
	}
}

The way you would read this is:

1. Resolve *.docker.label.local via the Docker API
2. If a container has a network labeled DO_NOT_RESOLVE, then don't return IPs with that network
3. If a container has a network named backend, then don't return IPs associated with that network

So if I try a dig <rawdns_container> app.tld then I would only receive the frontend IP.

Here's an example configuration blurb of what I've got in mind:

{
    "http.debian.net.": {
        "type": "static",
        "CNAME": [ "apt-cacher-ng.docker" ]
    },
    "my-new-tld.": {
        "type": "static",
        "A": [ "1.2.3.4", "5.6.7.8" ],
        "AAAA": [ "::1", "::2" ],
        "TXT": [ "lolololol" ]
    }
}

If a container is set to --net=host, it gets no IP, which is obviously less than helpful for us. We should be able to figure out something for this case, but exactly what would be "correct" here is debatable.

I've got a lot of 100% duplicated blocks in my configuration (because I MITM several .deb mirrors to my local apt-cacher-ng instance, exactly like https://github.com/tianon/rawdns/blob/b2cec4eeff1377afdfd8c90e5a4716eb82370a09/hacks/apt-cacher-ng.md, so whatever gets implemented here should be reflected there), so it'd be nice to have some way to say something like "configuration for this new host should be copied from that other host".

I see two main ways to implement this:

{
	"host1.": {
		...
	},
	"host2.": "host1."
}

Main pros: simple for users to write
Main cons: annoying to implement (StringOrDomainConfig, etc), inflexible for later enhancement

{
	"host1.": {
		...
	},
	"host2.": {
		"copy": "host1.",
		...
	}
}

(or "type": "copy", but I'm not sure I like that -- being able to change even the "type" of what we've copied from seems fun -- maybe "merge": "host1." is better to make it clear what's happening here)

Main pros: flexible, saves code from needing complex unmarshalling for StringOrDomainConfig
Main cons: slightly complex "merging" behavior

One thing to decide would be whether "cnames": [ "1.2.3.4" ] merged into "cnames": [ "5.6.7.8" ] becomes [ "5.6.7.8" ] or [ "1.2.3.4", "5.6.7.8" ].

After deploying rawdns (version 1.2~ds1-1 from debian) in a small sized docker environment - i got the following errors, just a fetr a few minutes of operation:

rawdns[34447]: 2015/09/18 13:03:08 error: failed to lookup container "test": failed HTTP request: Get http://unix-socket/v1.14/containers/rabbitmq/json: dial unix /var/run/docker.sock: too many open files

lsof shows that rawdns has consumed all the 1021 fd's.
The following small patch fixes the issue for me:

diff --git a/src/cmd/rawdns/docker.go b/src/cmd/rawdns/docker.go
index 94c3140..7d763a5 100644
--- a/src/cmd/rawdns/docker.go
+++ b/src/cmd/rawdns/docker.go
@@ -58,6 +58,7 @@ func httpClient(u *url.URL) *http.Client {
                transport.Dial = func(proto, addr string) (net.Conn, error) {
                        return net.Dial("unix", path)
                }
+               transport.DisableKeepAlives = true
                u.Scheme = "http"
                u.Host = "unix-socket"
                u.Path = ""

I noticed that the newest packaged version is 1.6 (in Stretch, Buster and Sid), would it be possible to update the package to version 1.7?

If the question type is ANY, all RRs should be in Answer, not Extra, regardless of their type.

As I've mentioned now in #25 (comment), I went to a talk about CoreDNS, specifically around flexibility (and doing "horrible" things with it), and I was really impressed.

I think it makes sense to see what it would take to replicate rawdns via CoreDNS (if anything -- maybe the fundamentals are already there!), since that would offer much more flexibility in the long run.

Using this in a project where rawdns gets 2-3 queries a second.

After around 24hrs I have observed rawdns and the docker daemon using several GB of memory. DNS lookups still work, and I can't find anything unusual in either docker or rawdns logs.

Not sure what other details or debug information I can provide.

System: Ubuntu 14.04, Docker 1.3.2, public rawdns image (6320427debfe)

Hi,

I noticed this TODO (

// TODO IPv6 support (when Docker itself has such a thing...)

Docker does support IPv6 (https://docs.docker.com/engine/userguide/networking/default_network/ipv6/) and, thusly, it would be great if this DNS implementation could serve AAAA records. I can also see that there is ".NetworkSettings.GlobalIPv6Address" provided in the response from [docker]/containers/web/json in ApiVersion 1.22 (and possibly before that version as well) that could be returned by this implementation.

Had you thought about the possibility of using container labels and dns?

In ubuntu 14.04 desktop I need to disable dnsmasq by commenting "dns=dnsmasq" in /etc/NetworkManager/NetworkManager.conf

I think that the readme should explain that other containers that want to access the rawdns service need to pass the docker0 host ip
--dns