NAME

       fs_exportafs - Configures export of AFS to clients of other file systems

SYNOPSIS

       fs exportafs -type <exporter name>
           [-start <start/stop translator (on | off)>]
           [-convert <convert from afs to unix mode (on | off)>]
           [-uidcheck <run on strict 'uid check' mode (on | off)>]
           [-submounts <allow nfs mounts to subdirs of /afs/.. (on | off)>]
           [-clipags <use client-assigned PAGs (on | off)>]
           [-pagcb <callback clients to get creds (on | off)>]
           [-help]

       fs exp -t <exporter name>
           [-st <start/stop translator (on | off)>]
           [-co <convert from afs to unix mode (on | off)>]
           [-u <run on strict 'uid check' mode (on | off)>]
           [-su <allow nfs mounts to subdirs of /afs/.. (on | off)>]
           [-cl <use client-assigned PAGs (on | off)>]
           [-p <callback clients to get creds (on | off)>]
           [-h]

DESCRIPTION

       The fs exportafs command sets (if the -start argument is provided) or reports (if it is
       omitted) whether the machine can reexport the AFS filespace to clients of a non-AFS file
       system. To control certain features of the translation protocol, use the following
       arguments:

       •   To control whether the UNIX group and other mode bits on an AFS file or directory are
           set to match the owner mode bits when it is exported to the non-AFS file system, use
           the -convert argument.

       •   To control whether tokens can be placed in a credential structure identified by a UID
           that differs from the local UID of the entity that is placing the tokens in the
           structure, use the -uidcheck argument. The most common use is to control whether
           issuers of the knfs command can specify a value for its -id argument that does not
           match their local UID on the NFS/AFS translator machine.

       •   To control whether users can create mounts in the non-AFS filespace to an AFS
           directory other than /afs, use the -submounts argument.

OPTIONS

       -type <exporter name>
           Names the alternate file system to which to reexport the AFS filespace. The only
           acceptable value is "nfs", in lowercase letters only.

       -start <on | off>
           Enables the local machine to reexport the AFS filespace if the value is "on", or
           disables it if the value is "off". Omit this argument to report the current setting
           for all of the configurable parameters.

       -convert <on | off>
           Controls the setting of the UNIX group and other mode bits on AFS files and
           directories exported to the non-AFS file system. If the value is "on", they are set to
           match the owner mode bits. If the value is "off", the bits are not changed. If this
           argument is omitted, the default value is "on".

       -uidcheck <on | off>
           Controls whether tokens can be placed in a credential structure identified by a UID
           that differs from the local UID of the entity that is placing the tokens in the
           structure.

           •   If the value is on, the UID that identifies the credential structure must match
               the local UID.

               With respect to the knfs command, this value means that the value of -id argument
               must match the issuer's local UID on the translator machine. In practice, this
               setting makes it pointless to include the -id argument to the knfs command,
               because the only acceptable value (the issuer's local UID) is already used when
               the -id argument is omitted.

               Enabling UID checking also makes it impossible to issue the klog and pagsh
               commands on a client machine of the non-AFS file system even though it is a system
               type supported by AFS. For an explanation, see klog(1).

           •   If the value is off (the default), tokens can be assigned to a local UID in the
               non-AFS file system that does not match the local UID of the entity assigning the
               tokens.

               With respect to the knfs command, it means that the issuer can use the -id
               argument to assign tokens to a local UID on the NFS client machine that does not
               match his or her local UID on the translator machine. (An example is assigning
               tokens to the MFS client machine's local superuser "root".) This setting allows
               more than one issuer of the knfs command to make tokens available to the same user
               on the NFS client machine. Each time a different user issues the knfs command with
               the same value for the -id argument, that user's tokens overwrite the existing
               ones. This can result in unpredictable access for the user on the NFS client
               machine.

       -submounts <on | off>
           Controls whether a user of the non-AFS filesystem can mount any directory in the AFS
           filespace other than the top-level /afs directory. If the value is "on", such
           submounts are allowed. If the value is "off", only mounts of the /afs directory are
           allowed. If this argument is omitted, the default value is "off".

       -clipags <on | off>
           Turning on this option enables support for "client-assigned PAGs". With client-
           assigned PAGs, an NFS client can manage its own AFS pags, and inform the NFS
           translator machine what PAG we are using, instead of the NFS translator machine
           keeping track of PAGs. An NFS client machine can do this if it has the "afspag" kernel
           module loaded, which tracks PAGs but otherwise does not implement AFS functionality,
           and forwards all requests to the NFS translator machine.

           You should only turn on this option if you are making use of client-assigned PAGs, and
           you trust the NFS client machines making use of the translator. This option is off by
           default.

       -pagcb <on | off>
           Turning on this option means that the NFS translator machine will contact new NFS
           clients in order to obtain their credentials and sysnames. This option can be useful
           so that client credentials are not lost if the translator machine is rebooted, or if
           an NFS client is "moved" to using a different translator. This functionality will only
           work with NFS clients that are also running the "afspag" kernel module.

           Using this option with NFS clients not running with the "afspag" kernel module would
           cause long timeouts when the translator machine attempts to contact the client to
           obtain its credentials and sysname list. This option is off by default.

       -help
           Prints the online help for this command. All other valid options are ignored.

OUTPUT

       If the machine is not even configured as a server of the non-AFS file system, the
       following message appears:

          Sorry, the <file_system>-exporter type is currently not supported on
          this AFS client

       If the machine is configured as a server of the non-AFS file system but is not currently
       enabled to reexport AFS to it (because the -start argument to this command is not set to
       "on"), the message is as follows:

          '<file_system>' translator is disabled

       If the machine is enabled to reexport AFS, the following message precedes messages that
       report the settings of the other parameters.

          '<file_system>' translator is enabled with the following options:

       The following messages indicate that the -convert argument is set to "on" or "off"
       respectively:

          Running in convert owner mode bits to world/other mode
          Running in strict unix mode

       The following messages indicate that the -uidcheck argument is set to "on" or "off"
       respectively:

          Running in strict 'passwd sync' mode
          Running in no 'passwd sync' mode

       The following messages indicate that the -submounts argument is set to "on" or "off"
       respectively:

          Allow mounts of /afs/.. subdirs
          Only mounts to /afs allowed

EXAMPLES

       The following example shows that the local machine can export AFS to NFS client machines.

          % fs exportafs nfs
          'nfs' translator is enabled with the following options:
               Running in convert owner mode bits to world/other mode
               Running in no 'passwd sync' mode
               Only mounts to /afs allowed

       The following example enables the machine as an NFS server and converts the UNIX group and
       other mode bits on exported AFS directories and files to match the UNIX owner mode bits.

          % fs exportafs -type nfs -start on -convert on

       The following example disables the machine from reexporting AFS to NFS client machines:

          % fs exportafs -type nfs -start off

PRIVILEGE REQUIRED

       The issuer must be logged in as the local superuser root.

SEE ALSO

       klog(1), knfs(1)

COPYRIGHT

       IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

       This documentation is covered by the IBM Public License Version 1.0.  It was converted
       from HTML to POD by software written by Chas Williams and Russ Allbery, based on work by
       Alf Wachsmann and Elizabeth Cassell.