NSS-MYHOSTNAME(8)						  nss-myhostname						 NSS-MYHOSTNAME(8)

NAME

       nss-myhostname - Provide hostname resolution for the locally configured system hostname.

SYNOPSIS

       nss-myhostname.la

DESCRIPTION

       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 gethostname(2). 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, myhostname has to be added to the line starting with "hosts:" in /etc/nsswitch.conf

       It is recommended to put 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.

EXAMPLE

	   # /etc/nsswitch.conf

	   passwd:	   compat
	   group:	   compat
	   shadow:	   compat

	   hosts:	   files dns 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
	   127.0.0.2	   STREAM
	   127.0.0.2	   DGRAM
	   127.0.0.2	   RAW

       In this case the local hostname is omega.

SEE ALSO

       systemd(1), systemd-logind.service(8), logind.conf(5), loginctl(1), pam.conf(5), pam.d(5), pam(8), pam_loginuid(8)

systemd 208															 NSS-MYHOSTNAME(8)