NAME

fs_getserverprefs - Displays preference ranks for File servers or Location servers

SYNOPSIS

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

DESCRIPTION

The fs getserverprefs command (alias fs gp) displays preference ranks for file server interfaces (File servers run the fileserver process) or, if the -vlserver flag is provided, for Location Servers (which run the vlserver process). For file servers, the Cache Manager tracks up to 15 interfaces per server and assigns a separate rank to each interface. The ranks indicate the order in which the Cache Manager attempts to contact the interfaces of servers that are hosting a volume when it needs to fetch data from the volume. For Location Servers, the ranks indicate the order in which the Cache Manager attempts to contact a cell's Location Servers when requesting volume location information. For both types of rank, lower integer values are preferred over higher values.

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 Location Server ranks range from 10,000 to 10,126. The Cache Manager assigns ranks to every machine listed in its configuration /etc/yfs/yfs-client.conf file or found via DNS SRV or DNS AFSDB records for the cell. When the Cache Manager needs to fetch volume location information from a cell, it compares the ranks for the Location Servers belonging to that cell, and attempts to contact the Location Server with the lowest integer rank. If the Cache Manager cannot reach the Location Server, it tries to contact the Location Server with the next lowest integer rank, and so on. If all of a cell's Location Servers are unavailable, the Cache Manager cannot fetch data from the cell.

Default File Server ranks range from 5,000 to 40,000; the maximum possible rank is 65,534. When the Cache Manager needs to fetch data from a volume, it compares the ranks for the network interfaces for File Servers that store the volume, and attempts to contact the interface that has the lowest integer rank. If it cannot reach the selected File Server interface, it tries to contact the interface with the next lowest integer rank, and so on. If it cannot reach any of the interfaces for File Servers that store the volume, it cannot fetch data from the volume.

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.

-noresolve

Displays the IP addresses of File Server or Location Server interfaces, rather than their hostnames. If this argument is not provided, the fs command interpreter has the IP addresses translated to hostnames such as fs1.your-cell-name.com.

-vlservers

Displays preference ranks for Location Server interfaces rather than File Server 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 interface or Location Server interface, pairing the server's hostname or IP address with its rank. The Cache Manager stores IP addresses in its kernel list of ranks, but the fs 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 -noresolve 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 cell named your-cell-name, 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, foreign-cell-name.com. It is not possible to translate the IP addresses of two machines on the 138.255 network.

   % fs getserverprefs
   fs2.your-cell-name.com          20007
   fs3.your-cell-name.com          30002
   fs1.your-cell-name.com          20011
   fs4.your-cell-name.com          30010
   server1.foreign-cell-name.com   40002
   10.255.33.34                    40000
   server6.foreign-cell-name.com   40012
   10.255.33.37                    40005

The following example shows hows the output displays IP addresses when the -noresolve 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 172.16.107.210, 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 -noresolve
   172.16.107.214                 20007
   172.16.105.99                  30002
   172.16.107.212                 20011
   172.16.105.100                 30010
   10.255.33.41                   40002
   10.255.33.34                   40000
   10.255.33.36                   40012
   10.255.33.37                   40005

The example shows how the -vlservers flag displays preference ranks for Location Server interfaces:

   % fs getserverprefs -vlservers
   fs2.your-cell-name.com        10052
   fs3.your-cell-name.com        10113
   fs1.your-cell-name.com        10005

PRIVILEGE REQUIRED

No special privileges are required for this command.

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.

ACKNOWLEDGEMENTS

"AFS" is a registered mark of International Business Machines Corporation, used under license. (USPTO Registration 1598389)

"OpenAFS" is a registered mark of International Business Machines Corporation. (USPTO Registration 4577045)

The "AuriStor" name, log 'S' brand mark, and icon are registered marks of AuriStor, Inc. (USPTO Registrations 4849419, 4849421, and 4928460) (EUIPO Registration 015539653).

"Your File System" is a registered mark of AuriStor, Inc. (USPTO Registrations 4801402 and 4849418).

"YFS" and "AuriStor File System" are trademarks of AuriStor, Inc.