3 BosConfig - Defines server processes for the BOS Server to monitor
7 The F<BosConfig> file lists the processes that the Basic OverSeer (BOS)
8 Server monitors on its server machine, and thus defines which AFS server
9 processes run on the machine. It specifies how the BOS Server reacts when
10 a process fails, and also defines the times at which the BOS Server
11 automatically restarts processes as part of performance maintenance. The
12 file must reside in the F</usr/afs/local> directory on each AFS server
15 A server process entry in the F<BosConfig> file records the following
22 The I<entry type>, which is one of the following:
28 Designates a server process that runs periodically instead of
29 continuously. The BOS Server starts a cron process only at specified
30 times, not whenever it fails. All standard AFS process entries except
31 C<fs> are simple (there are no standard cron processes).
35 Designates a group of interdependent server processes. If one of the
36 processes fails, the BOS Server must coordinate its restart with the
37 restart of the other processes in the group, possibly by stopping them
40 There is only one standard entry of this type, for which the conventional
41 name is C<fs>. It combines three server processes: the File Server
42 (B<fileserver> process), the Volume Server (B<volserver> process), and the
43 Salvager (B<salvager> process). These processes all operate on the same
44 data--the AFS data stored on an AFS server machine's F</vicep> partitions
45 and mounted in the AFS filespace--but in different ways. Grouping the
46 processes prevents them from attempting to access the same data
47 simultaneously, which can cause corruption.
49 During normal operation, the Salvager process is not active. If the File
50 Server process fails, however, the BOS Server stops the Volume Server
51 process and runs the Salvager process to correct any corruption that
52 resulted from the failure. (The administrator can also issue the B<bos
53 salvage> command to invoke the Salvager process.) If the Volume Server
54 fails, the BOS Server can restart it without stopping the File Server or
59 Designates a server process that runs independently of any other on the
60 server machine. If a simple process fails, the BOS Server does not have to
61 coordinate its restart with any other process.
67 The I<entry name>. The conventional name for an entry in the F<BosConfig>
68 file and the associated process matches the binary filename. When issuing
69 any B<bos> command that takes the B<-instance> argument, identify each
70 process by the name used in the F<BosConfig> file. For a list of the
71 names, see the B<bos create> reference page.
75 The process's I<status flag>, which determines whether the BOS Server
76 attempts to start the process in two cases: each time the BOS Server
77 itself restarts, and when the process fails. The F<BosConfig> file
78 currently uses a binary notation to indicate whether the BOS Server
79 attempts to restart the process as necessary or does not monitor it at
80 all. For the sake of clarity, the AFS documentation refers to the flags as
81 C<Run> and C<NotRun> instead. Only a system administrator, not the BOS
82 Server, can change the flag.
86 One or more I<command parameters> which the BOS Server invokes to start
87 the process or processes associated with the entry:
93 A C<cron> entry has two command parameters, the first the complete
94 pathname to the program, and the second the time at which the BOS Server
99 The C<fs> entry has three command parameters, each the complete pathname
100 to the B<fileserver>, B<volserver>, and B<salvager> programs, in that
105 A C<simple> entry has only one command parameter, the complete pathname to
112 In addition to server process entries, the F<BosConfig> file specifies the
113 times at which the BOS Server performs two types of automatic process
120 The I<general restart> time at which the BOS Server restarts itself and
121 then each process for which the entry in the F<BosConfig> file has status
122 flag C<Run>. The default setting is Sunday at 4:00 a.m.
126 The I<binary restart> time at which the BOS Server restarts any server
127 process for which the time stamp on the binary file in the F</usr/afs/bin>
128 directory is later than the last restart time for the process. The default
133 Although the F<BosConfig> file is in ASCII format, do not use a text
134 editor to alter it. Its format is subject to change and incorrectly
135 formatted entries can prevent server startup in ways that are difficult to
136 diagnose. Instead always use the appropriate commands from the B<bos>
143 The B<bos create> command to create an entry in the file and start the
148 The B<bos delete> command to remove an entry from the file after the B<bos
149 stop> command is used to stop the associated process.
153 The B<bos getrestart> command to display the times at which the BOS Server
154 performs automatic restarts.
158 The B<bos setrestart> command to set the times at which the BOS Server
159 performs automatic process restarts.
163 The B<bos start> command to change an entry's status flag to C<Run> and
164 start the associated process.
168 The B<bos status> command to display all processes listed in the file.
172 The B<bos stop> command to change an entry's status flag to C<NotRun> and
173 stop the associated process.
177 There are also bos commands that start and stop processes without changing
178 entries in the F<BosConfig> file. The BOS Server reads the F<BosConfig>
179 file only when it starts, transferring the information into its
180 memory. Thus a process's status as represented in the BOS Server's memory
181 can diverge from its status in the F<BosConfig> file. The following
182 commands change a process's status in the BOS Server's memory only:
188 The B<bos restart> command restarts a specified set of processes, all
189 processes, or all processes other than the BOS Server.
193 The B<bos shutdown> command stops a process.
197 The B<bos startup> command starts a process.
205 L<bos_getrestart(8)>,
207 L<bos_setrestart(8)>,
220 IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.
222 This documentation is covered by the IBM Public License Version 1.0. It was
223 converted from HTML to POD by software written by Chas Williams and Russ
224 Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.