bionic (5) BosConfig.5.gz

Provided by: openafs-fileserver_1.8.0~pre5-1ubuntu1.2_amd64 bug

NAME

       BosConfig - Defines server processes for the BOS Server to monitor

DESCRIPTION

       The BosConfig file lists the processes that the Basic OverSeer (BOS) Server monitors on its server
       machine, and thus defines which AFS server processes run on the machine. It specifies how the BOS Server
       reacts when a process fails, and also defines the times at which the BOS Server automatically restarts
       processes as part of performance maintenance.  The file must reside in the /var/lib/openafs/local
       directory on each AFS server machine.

       A server process entry in the BosConfig file records the following information:

       •   The entry type, which is one of the following:

           cron
               Designates a server process that runs periodically instead of continuously. The BOS Server starts
               a cron process only at specified times, not whenever it fails. All standard AFS process entries
               except "fs" are simple (there are no standard cron processes).

           fs  Designates a group of interdependent server processes. If one of the processes fails, the BOS
               Server must coordinate its restart with the restart of the other processes in the group, possibly
               by stopping them first.

               There is only one standard entry of this type, for which the conventional name is "fs". It
               combines three server processes: the File Server (fileserver process), the Volume Server
               (volserver process), and the Salvager (salvager process). These processes all operate on the same
               data--the AFS data stored on an AFS server machine's /vicep partitions and mounted in the AFS
               filespace--but in different ways. Grouping the processes prevents them from attempting to access
               the same data simultaneously, which can cause corruption.

               During normal operation, the Salvager process is not active. If the File Server process fails,
               however, the BOS Server stops the Volume Server process and runs the Salvager process to correct
               any corruption that resulted from the failure. (The administrator can also issue the bos salvage
               command to invoke the Salvager process.) If the Volume Server fails, the BOS Server can restart
               it without stopping the File Server or running the Salvager.

           simple
               Designates a server process that runs independently of any other on the server machine. If a
               simple process fails, the BOS Server does not have to coordinate its restart with any other
               process.

       •   The entry name. The conventional name for an entry in the BosConfig file and the associated process
           matches the binary filename. When issuing any bos command that takes the -instance argument, identify
           each process by the name used in the BosConfig file. For a list of the names, see the bos create
           reference page.

       •   The process's status flag, which determines whether the BOS Server attempts to start the process in
           two cases: each time the BOS Server itself restarts, and when the process fails. The BosConfig file
           currently uses a binary notation to indicate whether the BOS Server attempts to restart the process
           as necessary or does not monitor it at all. For the sake of clarity, the AFS documentation refers to
           the flags as "Run" and "NotRun" instead.  Only a system administrator, not the BOS Server, can change
           the flag.

       •   One or more command parameters which the BOS Server invokes to start the process or processes
           associated with the entry:

           •   A "cron" entry has two command parameters, the first the complete pathname to the program, and
               the second the time at which the BOS Server invokes the program.

           •   The "fs" entry has three command parameters, each the complete pathname to the fileserver,
               volserver, and salvager programs, in that order.

           •   A "simple" entry has only one command parameter, the complete pathname to the program.

       In addition to server process entries, the BosConfig file specifies the times at which the BOS Server
       performs two types of automatic process restarts:

       •   The general restart time at which the BOS Server restarts itself and then each process for which the
           entry in the BosConfig file has status flag "Run". The default setting is Sunday at 4:00 a.m.

       •   The binary restart time at which the BOS Server restarts any server process for which the time stamp
           on the binary file in the /usr/lib/openafs directory is later than the last restart time for the
           process. The default is 5:00 a.m.

       Finally, there is an entry specifying whether the BOS Server will start in restricted mode.

       Although the BosConfig file is in ASCII format, it is normally best not to use a text editor to alter it.
       The parser is very picky, and incorrectly formatted entries can prevent server startup in ways that are
       difficult to diagnose. Instead, use the appropriate commands from the bos command suite:

       •   The bos create command to create an entry in the file and start the associated process.

       •   The bos delete command to remove an entry from the file after the bos stop command is used to stop
           the associated process.

       •   The bos getrestart command to display the times at which the BOS Server performs automatic restarts.

       •   The bos getrestricted command to display whether the BOS Server is running in restricted mode.

       •   The bos setrestart command to set the times at which the BOS Server performs automatic process
           restarts.

       •   The bos setrestricted command to place the BOS Server in restricted mode.

       •   The bos start command to change an entry's status flag to "Run" and start the associated process.

       •   The bos status command to display all processes listed in the file.

       •   The bos stop command to change an entry's status flag to "NotRun" and stop the associated process.

       There are also bos commands that start and stop processes without changing entries in the BosConfig file.
       The BOS Server reads the BosConfig file only when it starts, transferring the information into its
       memory. Thus a process's status as represented in the BOS Server's memory can diverge from its status in
       the BosConfig file. The following commands change a process's status in the BOS Server's memory only:

       •   The bos restart command restarts a specified set of processes, all processes, or all processes other
           than the BOS Server.

       •   The bos shutdown command stops a process.

       •   The bos startup command starts a process.

       When the BOS Server shuts down, it rewrites BosConfig, discarding any changes made manually to that file.
       To change the configuration for the next BOS Server restart, instead write a new file to BosConfig.new.
       If BosConfig.new exists when the BOS Server starts, BosConfig will be replaced by BosConfig.new before
       the BOS Server reads its configuration.  Note that the BOS Server will notice a new BosConfig.new file
       whenever the general restart time is reached, if one is configured, since the BOS Server restarts itself
       at that time.

SEE ALSO

       bos_create(8), bos_delete(8), bos_getrestart(8), bos_getrestricted(8), bos_restart(8), bos_setrestart(8),
       bos_setrestricted(8), bos_shutdown(8), bos_start(8), bos_startup(8), bos_status(8), bos_stop(8),
       bos_salvage(8), fileserver(8), salvager(8), volserver(8)

       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.