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update-openssh-known-hosts(8)


NAME

   update-openssh-knwon-hosts - download, filter and merge known_hosts for
   OpenSSH

SYNOPSIS

   update-openssh-known-hosts [-f]

DESCRIPTION

   update-openssh-known-hosts manages downloading, filtering and  mergeing
   of  ssh_known_hosts  files from anywhere into one local file for use by
   ssh(1).

OPTIONS

   -f     treat every non-zero exit from download plugin as an error,  see
          EXIT_IGNORE below.

RETURN VALUES

   Returns zero on success and anything else on error.

ENVIRONMENT

   CONFDIR
          Configuration  directory,  defaults to /etc/openssh-known-hosts.
          Currently there is only a sources subdirectory in it.

   PLUGIN_PATH
          Plugin         search         path,         defaults          to
          /usr/local/share/openssh-known-hosts/plugins:/usr/share/openssh-known-hosts/plugins.

   CACHEDIR
          Cache directory, defaults to /var/cache/openssh-known-hosts.

   LOCK   Lockfile path, defaults to /var/lock/openssh-known-hosts.

   OUTFILE
          Output         file          name,          defaults          to
          /var/lib/openssh-known-hosts/ssh_known_hosts

SOURCE DEFINITIONS

   A source definition is shell snippet dropped into CONFDIR/sources/ with
   a run-parts(8) compliant name.  There are two variables not specific to
   a download plugin:

   PLUGIN name of the download plugin to use, searched for in PLUGIN_PATH.

   EXIT_IGNORE
          optional  space-seperated  list  of  exitcodes  which  should be
          ignored.  Upon such exit code the previously downloaded  version
          is used.

DOWNLOAD PLUGINS

   Download   plugins   are   executables  dropped  into  PLUGIN_PATH  and
   referenced via the PLUGIN variable in the source definition.  A  plugin
   gets  the  variables  set  in the source definition in its environment.
   The working directory will be set  to  the  source's  cache  directory.
   Everything  a  plugin  has  to  do  is  to  create  a file named "new".
   "current" must not be touched but  can  be  used  as  a  hint  to  skip
   downloading  the  same file again.  stdout and stderr will be connected
   to "log", which will be output on error.  Plugins needn't create  "new"
   if it would be identical to "current".

HOSTNAME FILTERS

   Place  a file foo.filter next to your source definition foo.  Each line
   shall contain a rule consisting of an action, a space  and  a  pattern.
   The  first  rule  with a matching pattern decides: If the action starts
   with a, o, p or y (for accept, admit, allow, ok, pass,  permit,  print,
   yes,  ...)  the hostname will be used, otherwise it is discarded.  If a
   key has no hostnames left it is discarded as a whole.

SEE ALSO

   ssh(1),   sshd(8),   ssh_config(5),   curl(1),    rsync(1),    psql(1),
   run-parts(8)

AUTHORS

   Timo Weingrtner <timo@tiwe.de>.

                              2014-02-03     UPDATE-OPENSSH-KNOWN-HOSTS(8)



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