From 549f55b104d68bdc7351ff3bc511e9ccadd84a3a Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Sat, 22 Oct 2016 18:04:45 -0400 Subject: ./tools/notsd-move --- src/nss-myhostname/nss-myhostname.xml | 148 ++++++++++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 src/nss-myhostname/nss-myhostname.xml (limited to 'src/nss-myhostname/nss-myhostname.xml') diff --git a/src/nss-myhostname/nss-myhostname.xml b/src/nss-myhostname/nss-myhostname.xml new file mode 100644 index 0000000000..a920ec334f --- /dev/null +++ b/src/nss-myhostname/nss-myhostname.xml @@ -0,0 +1,148 @@ + + + + + + + + + nss-myhostname + systemd + + + + Developer + Lennart + Poettering + lennart@poettering.net + + + + + + nss-myhostname + 8 + + + + nss-myhostname + libnss_myhostname.so.2 + Provide hostname resolution for the locally + configured system hostname. + + + + libnss_myhostname.so.2 + + + + Description + + nss-myhostname is a plug-in module 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 + gethostname2. The precise + hostnames resolved by this module are: + + + The local, configured hostname is resolved to + all locally configured IP addresses ordered by their scope, 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). + + The hostnames localhost and + localhost.localdomain (as well as any hostname + ending in .localhost or .localhost.localdomain) + are resolved to the IP addresses 127.0.0.1 and ::1. + + The hostname gateway is + resolved to all current default routing gateway addresses, + ordered by their metric. This assigns a stable hostname to the + current gateway, useful for referencing it independently of the + current network configuration state. + + + 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, add myhostname to the line starting with + hosts: in /etc/nsswitch.conf. + + It is recommended to place myhostname last in the nsswitch.conf' + hosts: line to make sure that this mapping is only used as fallback, and that any DNS or + /etc/hosts based mapping takes precedence. + + + + Example + + Here is an example /etc/nsswitch.conf file that enables + nss-myhostname correctly: + +passwd: compat mymachines +group: compat mymachines +shadow: compat + +hosts: files mymachines resolve 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 + + systemd1, + nss-resolve8, + nss-mymachines8, + nsswitch.conf5, + getent1 + + + + -- cgit v1.2.3-54-g00ecf