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FS_GETSERVERPREFS(1)	     AFS Command Reference	  FS_GETSERVERPREFS(1)

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
       /usr/local/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.

OpenAFS				  2016-12-14		  FS_GETSERVERPREFS(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OUTPUT | EXAMPLES | PRIVILEGE REQUIRED | SEE ALSO | COPYRIGHT

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