IMPORT(4)                                               IMPORT(4)

     NAME
          import - import a name space from a remote system

     SYNOPSIS
          import [ options ] system file [ mountpoint ]

          import -m [ options ] system mountpoint

          import -B [ options ] mountpoint [ cmd [ args ... ] ]

     DESCRIPTION
          Import allows an arbitrary file on a remote system to be
          imported into the local name space.  Usually file is a
          directory, so the complete file tree under the directory is
          made available.

          A process is started on the remote machine, with authority
          of the user of import, to perform work for the local machine
          using the exportfs(4) service.  The default port used is TCP
          17007.  If mountpoint is omitted import uses the name of the
          remote file as the local mount point.

          The options are:

          -a -b -c -C Control the construction of union directories,
                      as in mount and bind(1). Only valid when file is
                      a directory.

          -A          Skip the authentication protocol.  This is use-
                      ful for connecting to foreign systems like
                      Inferno.

          -B          Run in ``backwards'' mode, described below.

          -E enc      Push an authentication protocol on its network
                      connection.  The supported protocols are clear
                      (the default, no protocol) and ssl.  There are
                      plans to make tls available.

          -e 'enc auth'
                      Specify the encryption and authentication algo-
                      rithms to use for encrypting the wire traffic
                      (see ssl(3)). The defaults are rc4_256 and sha1.

          -k keypattern
                      Use keypattern to select a key to authenticate
                      to the remote side (see auth(2)).

          -o -O       These equivalent flags run import in a pre-

     IMPORT(4)                                               IMPORT(4)

                      9P2000 compatibility mode to import from ancient
                      servers.

          -p          Push the aan(8) filter onto the connection to
                      protect against temporary network outages.

          -s name     Post the connection's mountable file descriptor
                      as /srv/name.

          The -m option mounts a file exported by exportfs(4) with its
          -r or -S options, which skip the part of its protocol that
          allows the importer to specify the file to export.  Instead,
          the file or name space is selected by exportfs, and import
          mounts it on mountpoint as guided by the other options.

          The -B option runs import in ``backwards'' mode.  In this
          mode, import runs a p9any authentication (as server) over
          its file descriptor 0 (expected to be an incoming network
          connection from exportfs -B), mounts the connection onto
          mntpt, and optionally runs cmd args.

     EXAMPLES
          Assume a machine kremvax that has IP interfaces for the com-
          pany intranet and the global internet mounted on /net and
          /net.alt respectively.  Any machine inside the company can
          get telnet out to the global internet using:

               import -a kremvax /net.alt
               telnet /net.alt/tcp!ucbvax

          Suppose that the machine moscvax has access to a private
          file server containing public web pages that need to be
          served by the less-trusted server webvax.  Webvax runs the
          following listener (see listen(8)) on TCP port 999:

               #!/bin/rc
               import -B -s rowebfs /usr/web /bin/restarthttpd

          When moscvax boots, it runs

               exportfs -R -r /usr/web -B tcp!webvax!999

          to serve a read-only copy of /usr/web to webvax.  When
          webvax gets the call, import mounts the served tree onto its
          own /usr/web and then runs /bin/restarthttpd to restart
          httpd(8).

     SOURCE
          /sys/src/cmd/import.c

     SEE ALSO
          bind(1), ssl(3), exportfs(4), srv(4), aan(8), listen(8), cs

     IMPORT(4)                                               IMPORT(4)

          in ndb(8)