nss-myhostname man page

nss-myhostname, libnss_myhostname.so.2 — Provide hostname resolution for the locally configured system hostname.




nss-myhostname is a plugin for the GNU Name Service Switch (NSS) functionality of the GNU C Library (glibc) primarily providing hostname resolution for the locally configured system hostname as returned by gethostname(2). The precise hostnames resolved by this module are:

Various software relies on an always-resolvable local hostname. When using dynamic hostnames, this is traditionally achieved by patching /etc/hosts at the same time as changing the hostname. This is problematic since it requires a writable /etc file system and is fragile because the file might be edited by the administrator at the same time. With nss-myhostname enabled changing /etc/hosts is unnecessary, and on many systems the file becomes entirely optional.

To activate the NSS modules, myhostname has to be added to the line starting with hosts: in /etc/nsswitch.conf.

It is recommended to place myhostname last in the nsswitch.conf line to make sure that this mapping is only used as fallback, and any DNS or /etc/hosts based mapping takes precedence.


Here's an example /etc/nsswitch.conf file, that enables myhostname correctly:

passwd:   compat
group:    compat
shadow:   compat

hosts:    files dns mymachines myhostname
networks:       files

protocols:      db files
services:       db files
ethers:   db files
rpc:      db files

netgroup:       nis

To test, use glibc's getent tool:

$ getent ahosts `hostname`
::1       STREAM omega
::1       DGRAM
::1       RAW       STREAM       DGRAM       RAW

In this case the local hostname is omega.

See Also

systemd(1), nss-mymachines(8), nsswitch.conf(5), getent(1)

Referenced By

nss-mymachines(8), nss-resolve(8), systemd.directives(7), systemd.index(7).

Explore man page connections for nss-myhostname(8).

libnss_myhostname.so.2(8) is an alias of nss-myhostname(8).