разрешение имени хоста через systemd-resolved.service (Hostname resolution via systemd-resolved.service)
Имя (Name)
nss-resolve, libnss_resolve.so.2 - Hostname resolution via
systemd-resolved.service
Синопсис (Synopsis)
libnss_resolve.so.2
Описание (Description)
nss-resolve
is a plug-in module for the GNU Name Service Switch
(NSS) functionality of the GNU C Library (glibc
) enabling it to
resolve hostnames via the systemd-resolved(8) local network name
resolution service. It replaces the nss-dns
plug-in module that
traditionally resolves hostnames via DNS.
To activate the NSS module, add "resolve [!UNAVAIL=return]" to
the line starting with "hosts:" in /etc/nsswitch.conf.
Specifically, it is recommended to place "resolve" early in
/etc/nsswitch.conf's "hosts:" line. It should be before the
"files" entry, since systemd-resolved supports /etc/hosts
internally, but with caching. To the contrary, it should be after
"mymachines", to give hostnames given to local VMs and containers
precedence over names received over DNS. Finally, we recommend
placing "dns" somewhere after "resolve", to fall back to nss-dns
if systemd-resolved.service is not available.
Note that systemd-resolved
will synthesize DNS resource records
in a few cases, for example for "localhost" and the current local
hostname, see systemd-resolved(8) for the full list. This
duplicates the functionality of nss-myhostname(8), but it is
still recommended (see examples below) to keep nss-myhostname
configured in /etc/nsswitch.conf, to keep those names resolveable
if systemd-resolved
is not running.
Please keep in mind that nss-myhostname
(and nss-resolve
) also
resolve in the other direction — from locally attached IP
addresses to hostnames. If you rely on that lookup being provided
by DNS, you might want to order things differently.
Примеры (Examples)
Here is an example /etc/nsswitch.conf file that enables
nss-resolve
correctly:
passwd: compat systemd
group: compat [SUCCESS=merge] systemd
shadow: compat systemd
gshadow: files systemd
hosts: mymachines resolve [!UNAVAIL=return]
files myhostname dns
networks: files
protocols: db files
services: db files
ethers: db files
rpc: db files
netgroup: nis
Смотри также (See also)
systemd(1), systemd-resolved(8), nss-systemd(8),
nss-myhostname(8), nss-mymachines(8), nsswitch.conf(5)