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NAME

       fs_getserverprefs - Displays preference ranks for file servers or VL
       servers

SYNOPSIS

       fs getserverprefs [-file <output to named file>]
           [-numeric] [-vlservers] [-help]

       fs gets [-f <output to named file>] [-n] [-v] [-h]

       fs gp [-f <output to named file>] [-n] [-v] [-h]

DESCRIPTION

       The fs getserverprefs command displays preference ranks for file server
       machine interfaces (file server machines run the fs process) or, if the
       -vlserver flag is provided, for Volume Location (VL) Server machines
       (which run the vlserver process). For file server machines, the Cache
       Manager tracks up to 15 interfaces per machine and assigns a separate
       rank to each interface. The ranks indicate the order in which the local
       Cache Manager attempts to contact the interfaces of machines that are
       housing a volume when it needs to fetch data from the volume. For VL
       Server machines, the ranks indicate the order in which the Cache
       Manager attempts to contact a cell's VL Servers when requesting VLDB
       information. For both types of rank, lower integer values are more
       preferred.

       The Cache Manager stores ranks in kernel memory. Once set, a rank
       persists until the machine reboots, or until the fs setserverprefs
       command is used to change it. fs_setserverprefs(1) explains how the
       Cache Manager sets default ranks, and how to use that command to change
       the default values.

       Default VL Server ranks range from 10,000 to 10,126. The Cache Manager
       assigns ranks to every machine listed in its copy of the
       /etc/openafs/CellServDB file or found via DNS AFSDB or SRV records for
       the cell when it initializes. When the Cache Manager needs to fetch
       VLDB information from a cell, it compares the ranks for the VL Server
       machines belonging to that cell, and attempts to contact the VL Server
       with the lowest integer rank. If the Cache Manager cannot reach the VL
       Server (because of server process, machine or network outage), it tries
       to contact the VL Server with the next lowest integer rank, and so on.
       If all of a cell's VL Server machines are unavailable, the Cache
       Manager cannot fetch data from the cell.

       Default file server ranks range from 5,000 to 40,000, excluding the
       range used for VL Servers (10,000 to 10,126); the maximum possible rank
       is 65,534. When the Cache Manager needs to fetch data from a volume, it
       compares the ranks for the interfaces of machines that house the
       volume, and attempts to contact the interface that has the lowest
       integer rank. If it cannot reach the fileserver process via that
       interface (because of server process, machine or network outage), it
       tries to contact the interface with the next lowest integer rank, and
       so on. If it cannot reach any of the interfaces for machines that house
       the volume, it cannot fetch data from the volume.

       For both file server machines and VL Server machines, it is possible
       for a machine or interface in a foreign cell to have the same rank as a
       machine or interface in the local cell. This does not present a
       problem, because the Cache Manager only ever compares ranks for
       machines belonging to one cell at a time.

OPTIONS

       -file <output file>
           Specifies the full pathname of a file to which to write the
           preference ranks. If the specified file already exists, the command
           overwrites its contents. If the pathname is invalid, the command
           fails. If this argument is not provided, the preference ranks
           appear on the standard output stream.

       -numeric
           Displays the IP addresses of file server machine interfaces or VL
           Server machines, rather than their hostnames. If this argument is
           not provided, the fs command interpreter has the IP addresses
           translated to hostnames such as "fs1.abc.com".

       -vlservers
           Displays preference ranks for VL Server machines rather than file
           server machine interfaces.

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

OUTPUT

       The output consists of a separate line for each file server machine
       interface or VL Server machine, pairing the machine's hostname or IP
       address with its rank. The Cache Manager stores IP addresses in its
       kernel list of ranks, but the command by default identifies interfaces
       by hostname, by calling a translation routine that refers to either the
       cell's name service (such as the Domain Name Server) or the local host
       table. If an IP address appears in the output, it is because the
       translation attempt failed. To bypass the translation step and display
       IP addresses rather than hostnames, include the -numeric flag. This can
       significantly speed the production of output.

       By default, the command writes to the standard output stream. Use the
       -file argument to write the output to a file instead.

EXAMPLES

       The following example displays the local Cache Manager's preference
       ranks for file server machines. The local machine belongs to the AFS
       cell named abc.com, and in this example the ranks of file server
       machines in its local cell are lower than the ranks of file server
       machines from the foreign cell, "def.com". It is not possible to
       translate the IP addresses of two machines on the 138.255 network.

          % fs getserverprefs
          fs2.abc.com           20007
          fs3.abc.com           30002
          fs1.abc.com           20011
          fs4.abc.com           30010
          server1.def.com       40002
          138.255.33.34         40000
          server6.def.com       40012
          138.255.33.37         40005

       The following example shows hows the output displays IP addresses when
       the -numeric flag is included, and illustrates how network proximity
       determines default ranks (as described on the fs setserverprefs
       reference page). The local machine has IP address 192.12.107.210, and
       the two file server machines on its subnetwork have ranks of 20,007 and
       20,011. The two file server machines on a different subnetwork of the
       local machine's network have higher ranks, 30,002 and 30,010, whereas
       the ranks of the remaining machines range from 40,000 to 40,012 because
       they are in a completely different network.

          % fs getserverprefs -numeric
          192.12.107.214          20007
          192.12.105.99           30002
          192.12.107.212          20011
          192.12.105.100          30010
          138.255.33.41           40002
          138.255.33.34           40000
          138.255.33.36           40012
          138.255.33.37           40005

       The example shows how the -vlservers flag displays preference ranks for
       VL Server machines:

          % fs getserverprefs -vlservers
          fs2.abc.com            10052
          fs3.abc.com            10113
          fs1.abc.com            10005

PRIVILEGE REQUIRED

       None

SEE ALSO

       fs_setserverprefs(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.



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