1 <?xml version="1.0" encoding="UTF-8"?>
2 <refentry id="BosConfig5">
4 <refentrytitle>BosConfig</refentrytitle>
5 <manvolnum>5</manvolnum>
8 <refname>BosConfig</refname>
9 <refpurpose>Defines server processes for the BOS Server to monitor</refpurpose>
12 <title>Description</title>
13 <para>The <replaceable>BosConfig</replaceable> file lists the processes that the Basic OverSeer (BOS)
14 Server monitors on its server machine, and thus defines which AFS server
15 processes run on the machine. It specifies how the BOS Server reacts when
16 a process fails, and also defines the times at which the BOS Server
17 automatically restarts processes as part of performance maintenance. The
18 file must reside in the <replaceable>/usr/afs/local</replaceable> directory on each AFS server
21 <para>A server process entry in the <replaceable>BosConfig</replaceable> file records the following
26 <para>The <emphasis>entry type</emphasis>, which is one of the following:</para>
32 <para>Designates a server process that runs periodically instead of
33 continuously. The BOS Server starts a cron process only at specified
34 times, not whenever it fails. All standard AFS process entries except
35 <computeroutput>fs</computeroutput> are simple (there are no standard cron processes).</para>
42 <para>Designates a group of interdependent server processes. If one of the
43 processes fails, the BOS Server must coordinate its restart with the
44 restart of the other processes in the group, possibly by stopping them
47 <para>There is only one standard entry of this type, for which the conventional
48 name is <computeroutput>fs</computeroutput>. It combines three server processes: the File Server
49 (<emphasis role="bold">fileserver</emphasis> process), the Volume Server (<emphasis role="bold">volserver</emphasis> process), and the
50 Salvager (<emphasis role="bold">salvager</emphasis> process). These processes all operate on the same
51 data--the AFS data stored on an AFS server machine's <replaceable>/vicep</replaceable> partitions
52 and mounted in the AFS filespace--but in different ways. Grouping the
53 processes prevents them from attempting to access the same data
54 simultaneously, which can cause corruption.</para>
56 <para>During normal operation, the Salvager process is not active. If the File
57 Server process fails, however, the BOS Server stops the Volume Server
58 process and runs the Salvager process to correct any corruption that
59 resulted from the failure. (The administrator can also issue the <emphasis role="bold">bos
60 salvage</emphasis> command to invoke the Salvager process.) If the Volume Server
61 fails, the BOS Server can restart it without stopping the File Server or
62 running the Salvager.</para>
69 <para>Designates a server process that runs independently of any other on the
70 server machine. If a simple process fails, the BOS Server does not have to
71 coordinate its restart with any other process.</para>
78 <para>The <emphasis>entry name</emphasis>. The conventional name for an entry in the <replaceable>BosConfig</replaceable>
79 file and the associated process matches the binary filename. When issuing
80 any <emphasis role="bold">bos</emphasis> command that takes the <emphasis role="bold">-instance</emphasis> argument, identify each
81 process by the name used in the <replaceable>BosConfig</replaceable> file. For a list of the
82 names, see the <emphasis role="bold">bos create</emphasis> reference page.</para>
86 <para>The process's <emphasis>status flag</emphasis>, which determines whether the BOS Server
87 attempts to start the process in two cases: each time the BOS Server
88 itself restarts, and when the process fails. The <replaceable>BosConfig</replaceable> file
89 currently uses a binary notation to indicate whether the BOS Server
90 attempts to restart the process as necessary or does not monitor it at
91 all. For the sake of clarity, the AFS documentation refers to the flags as
92 <computeroutput>Run</computeroutput> and <computeroutput>NotRun</computeroutput> instead. Only a system administrator, not the BOS
93 Server, can change the flag.</para>
97 <para>One or more <emphasis>command parameters</emphasis> which the BOS Server invokes to start
98 the process or processes associated with the entry:</para>
102 <para>A <computeroutput>cron</computeroutput> entry has two command parameters, the first the complete
103 pathname to the program, and the second the time at which the BOS Server
104 invokes the program.</para>
108 <para>The <computeroutput>fs</computeroutput> entry has three command parameters, each the complete pathname
109 to the <emphasis role="bold">fileserver</emphasis>, <emphasis role="bold">volserver</emphasis>, and <emphasis role="bold">salvager</emphasis> programs, in that
114 <para>A <computeroutput>simple</computeroutput> entry has only one command parameter, the complete pathname to
121 <para>In addition to server process entries, the <replaceable>BosConfig</replaceable> file specifies the
122 times at which the BOS Server performs two types of automatic process
127 <para>The <emphasis>general restart</emphasis> time at which the BOS Server restarts itself and
128 then each process for which the entry in the <replaceable>BosConfig</replaceable> file has status
129 flag <computeroutput>Run</computeroutput>. The default setting is Sunday at 4:00 a.m.</para>
133 <para>The <emphasis>binary restart</emphasis> time at which the BOS Server restarts any server
134 process for which the time stamp on the binary file in the <replaceable>/usr/afs/bin</replaceable>
135 directory is later than the last restart time for the process. The default
140 <para>Although the <replaceable>BosConfig</replaceable> file is in ASCII format, do not use a text
141 editor to alter it. Its format is subject to change and incorrectly
142 formatted entries can prevent server startup in ways that are difficult to
143 diagnose. Instead always use the appropriate commands from the <emphasis role="bold">bos</emphasis>
144 command suite:</para>
148 <para>The <emphasis role="bold">bos create</emphasis> command to create an entry in the file and start the
149 associated process.</para>
153 <para>The <emphasis role="bold">bos delete</emphasis> command to remove an entry from the file after the <emphasis role="bold">bos
154 stop</emphasis> command is used to stop the associated process.</para>
158 <para>The <emphasis role="bold">bos getrestart</emphasis> command to display the times at which the BOS Server
159 performs automatic restarts.</para>
163 <para>The <emphasis role="bold">bos setrestart</emphasis> command to set the times at which the BOS Server
164 performs automatic process restarts.</para>
168 <para>The <emphasis role="bold">bos start</emphasis> command to change an entry's status flag to <computeroutput>Run</computeroutput> and
169 start the associated process.</para>
173 <para>The <emphasis role="bold">bos status</emphasis> command to display all processes listed in the file.</para>
177 <para>The <emphasis role="bold">bos stop</emphasis> command to change an entry's status flag to <computeroutput>NotRun</computeroutput> and
178 stop the associated process.</para>
182 <para>There are also bos commands that start and stop processes without changing
183 entries in the <replaceable>BosConfig</replaceable> file. The BOS Server reads the <replaceable>BosConfig</replaceable>
184 file only when it starts, transferring the information into its
185 memory. Thus a process's status as represented in the BOS Server's memory
186 can diverge from its status in the <replaceable>BosConfig</replaceable> file. The following
187 commands change a process's status in the BOS Server's memory only:</para>
191 <para>The <emphasis role="bold">bos restart</emphasis> command restarts a specified set of processes, all
192 processes, or all processes other than the BOS Server.</para>
196 <para>The <emphasis role="bold">bos shutdown</emphasis> command stops a process.</para>
200 <para>The <emphasis role="bold">bos startup</emphasis> command starts a process.</para>
206 <title>See Also</title>
207 <para><link linkend="bos_create8">bos_create(8)</link>,
208 <link linkend="bos_delete8">bos_delete(8)</link>,
209 <link linkend="bos_getrestart8">bos_getrestart(8)</link>,
210 <link linkend="bos_restart8">bos_restart(8)</link>,
211 <link linkend="bos_setrestart8">bos_setrestart(8)</link>,
212 <link linkend="bos_shutdown8">bos_shutdown(8)</link>,
213 <link linkend="bos_start8">bos_start(8)</link>,
214 <link linkend="bos_startup8">bos_startup(8)</link>,
215 <link linkend="bos_status8">bos_status(8)</link>,
216 <link linkend="bos_stop8">bos_stop(8)</link>,
217 <link linkend="bos_salvage8">bos_salvage(8)</link>,
218 <link linkend="fileserver8">fileserver(8)</link>,
219 <link linkend="salvager8">salvager(8)</link>,
220 <link linkend="volserver8">volserver(8)</link></para>
224 <title>Copyright</title>
225 <para>IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.</para>
227 <para>This documentation is covered by the IBM Public License Version 1.0. It was
228 converted from HTML to POD by software written by Chas Williams and Russ
229 Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.</para>