nss-myhostname — 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)
providing hostname resolution for the locally configured system
hostname as returned by
Various software relies on an always-resolvable local hostname. When
using dynamic hostnames, this is usually achieved by patching
/etc/hosts at the same time as changing the host
name. This however is not ideal since it requires a writable
/etc file system and is fragile because the file
might be edited by the administrator at the same time. nss-myhostname
simply returns all locally configured public IP addresses, or, if none
are configured, the IPv4 address 127.0.0.2 (which is on the local
loopback) and the IPv6 address ::1 (which is the local host) for
whatever system hostname is configured locally. Patching
/etc/hosts is thus no longer necessary.
To activate the NSS modules,
has to be added to the line starting with "
It is recommended to put
last in the
nsswitch.conf line to make
sure that this mapping is only used as fallback, and any DNS
/etc/hosts based mapping takes precedence.
# /etc/nsswitch.conf passwd: compat group: compat shadow: compat hosts: files dns
myhostnamenetworks: 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 127.0.0.2 STREAM 127.0.0.2 DGRAM 127.0.0.2 RAW
In this case the local hostname is