Provided by: openafs-client_1.8.2-1ubuntu0.1_amd64 bug

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.example.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 example.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, "example.net". It is not possible to translate the
       IP addresses of two machines on the 138.255 network.

          % fs getserverprefs
          fs2.example.com       20007
          fs3.example.com       30002
          fs1.example.com       20011
          fs4.example.com       30010
          server1.example.net   40002
          138.255.33.34         40000
          server6.example.net   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.example.com        10052
          fs3.example.com        10113
          fs1.example.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.