groner / nss-docker

NSS module for finding Docker containers

This is a plugin for the GNU Name Service Switch (NSS) functionality of the GNU C Library (glibc) providing mechanism for finding Docker containers by theirs IDs.

The container names are searched in virtual domain name ".docker".

Install it and add this library to your /etc/nsswitch.conf file:

hosts: files docker [NOTFOUND=return] dns

Then try:

$ docker run -d --name test dex4er/alpine-init
a548fba14c314e77a1630580f6536e09002d84e5610b85a08c622fa451a4f893

$ getent hosts test.docker
172.17.0.4      test.docker

$ ping test.docker
PING test.docker (172.17.0.4) 56(84) bytes of data.
64 bytes from 172.17.0.4: icmp_seq=1 ttl=64 time=0.171 ms

This module does not require any additional libraries beside GNU C Library.

Installation

From source archive:

Check the number of the latest release: https://github.com/dex4er/nss-docker/releases/latest

Then (ie. for 0.01 release):

$ curl -L https://github.com/dex4er/nss-docker/archive/0.01.tar.gz | tar zxv
$ ./configure --prefix=/usr
$ make
$ sudo make install

From Git repository:

$ git clone https://github.com/dex4er/nss-docker
$ ./autogen.sh
$ ./configure --prefix=/usr
$ make
$ sudo make install

Testing

The tests requires root priviliges (for real chroot because /etc/nsswitch.conf can't be changed to another file)

It is suggested to compile necessary files (ie.: mock server) as standard user and run tests as root user.

$ make -C test check-src
$ sudo make test