nss-resolve(8) — Linux manual page


NSS-RESOLVE(8)                   nss-resolve                  NSS-RESOLVE(8)

NAME         top

       nss-resolve, libnss_resolve.so.2 - Hostname resolution via

SYNOPSIS         top


DESCRIPTION         top

       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.

EXAMPLE         top

       Here is an example /etc/nsswitch.conf file that enables nss-resolve

           passwd:         compat systemd
           group:          compat [SUCCESS=merge] systemd
           shadow:         compat

           hosts:          mymachines resolve [!UNAVAIL=return] files myhostname dns
           networks:       files

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

           netgroup:       nis

SEE ALSO         top

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

COLOPHON         top

       This page is part of the systemd (systemd system and service manager)
       project.  Information about the project can be found at 
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have a bug
       report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.  This
       page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2020-09-18.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2020-09-18.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to man-pages@man7.org

systemd 246                                                   NSS-RESOLVE(8)

Pages that refer to this page: 30-systemd-environment-d-generator(7)systemd.directives(7)systemd.index(7)libnss_myhostname.so.2(8)libnss_mymachines.so.2(8)libnss_systemd.so.2(8)nss-myhostname(8)nss-mymachines(8)nss-systemd(8)systemd-resolved(8)systemd-resolved.service(8)