nss-docker(8) 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".

The Docker API webservice has to be available as /var/run/docker.sock socket for current user. Usually it requires to add the user to "docker" system group.

To activate this NSS module, the "docker" module has to be added to /etc/nsswitch.conf file in "hosts:" line.

It is recommended to put the "docker" module after "files" module and before "dns" module. "[NOTFOUND=return]" setting is recommended before "dns" module to prevent using DNS as fallback if the container ID is not found.



hosts: files docker [NOTFOUND=return] dns


The container ID can't be longer than "getconf HOST_NAME_MAX" (64 for Linux).

The container ID are case sensitive. It means that "test.docker" and "Test.docker" can return different IP addresses.

Only IPv4 addresses are supported.


If you find the bug or want to implement new features, please report it at <https://github.com/dex4er/nss-docker/issues>


Copyright (c) 2015 Piotr Roszatycki <[email protected]>


nss-docker is distributed under the GNU Lesser General Public License (LGPL 2.1 or greater).