-
- This Source Code Form is subject to the terms of the Mozilla Public
- License, v. 2.0. If a copy of the MPL was not distributed with this
- - file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ - file, you can obtain one at http://mozilla.org/MPL/2.0/.
-->
<!-- Converted by db4-upgrade version 1.1 -->
<chapter xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="kea-lfc">
- <title>The LFC process</title>
+ <title>The LFC Process</title>
<section xml:id="kea-lfc-overview">
<title>Overview</title>
<para><command>kea-lfc</command> is a service process that removes
redundant information from the files used to provide persistent storage
- for the memfile data base backend. This service is written to run as a
- stand alone process.
+ for the memfile database backend. This service is written to run as a
+ standalone process.
</para>
<para>While <command>kea-lfc</command> can be started externally, there is
- usually no need to do this. <command>kea-lfc</command> is run on a periodic
+ usually no need to do this. <command>kea-lfc</command> is run on a periodic
basis by the Kea DHCP servers.
</para>
- <para>The process operates on a set of files, using them for input and output
- of the lease entries and to indicate where it is in the process in case of an
- interruption. Currently the caller must supply names for all of the files, in
- the future this requirement may be relaxed with the process getting the names
- from either the configuration file or from defaults.
+ <para>The process operates on a set of files, using them to receive input and output
+ of the lease entries and to indicate what stage the process is in, in the event of an
+ interruption. Currently the caller must supply names for all of the files.
</para>
</section>
<section xml:id="kea-lfc-usage">
- <title>Command Line Options</title>
+ <title>Command-Line Options</title>
<para><command>kea-lfc</command> is run as follows:
<screen>
kea-lfc [-4 | -6] -c config-file -p pid-file -x previous-file -i copy-file -o output-file -f finish-file
version of the lease files.
</para>
- <para>The <command>-c</command> argument specifies the configuration file. This is
- required, but not currently used by the process.
+ <para>The <command>-c</command> argument specifies the configuration file. This is
+ required, but is not currently used by the process.
</para>
<para>The <command>-p</command> argument specifies the PID file. When the
- <command>kea-lfc</command> process starts it attempts to determine if another
- instance of the process is already running by examining the pid file. If one
- is already running the new process is terminated. If one isn't running it writes
+ <command>kea-lfc</command> process starts, it attempts to determine whether another
+ instance of the process is already running by examining the pid file. If one
+ is already running, the new process is terminated; if one is not running, Kea writes
its pid into the pid file.
</para>
<para>The other filenames specify where the <command>kea-lfc</command> process
- should look for input, write its output and use for bookkeeping.
+ should look for input, write its output, and perform its bookkeeping:
<itemizedlist>
<listitem><simpara>
<command>previous</command> —
- When <command>kea-lfc</command> starts this
+ When <command>kea-lfc</command> starts, this
is the result of any previous run of <command>kea-lfc</command>.
- When <command>kea-lfc</command> finishes it is the result of this run.
+ When <command>kea-lfc</command> finishes, it is the result of this run.
If <command>kea-lfc</command> is interrupted before completing,
this file may not exist.
</simpara></listitem>
<listitem><simpara>
<command>input</command> —
- Before the DHCP server invokes <command>kea-lfc</command> it will
+ Before the DHCP server invokes <command>kea-lfc</command>, it will
move the current lease file here and then call <command>kea-lfc</command>
with this file.
</simpara></listitem>
<listitem><simpara>
<command>output</command> —
- The temporary file <command>kea-lfc</command> should use to write the leases.
+ This is the temporary file where <command>kea-lfc</command> writes the leases.
Upon completion of writing this file, it will be moved to the finish file
(see below).
</simpara></listitem>
<listitem><simpara>
<command>finish</command> —
- Another temporary file <command>kea-lfc</command> uses for bookkeeping. When
- <command>kea-lfc</command> completes writing the outputfile it moves it to this
- file name. After <command>kea-lfc</command> finishes deleting the other files
- (previous and input) it moves this file to previous lease file. By moving the
- files in this fashion the <command>kea-lfc</command> and the DHCP server
+ This is another temporary file <command>kea-lfc</command> uses for bookkeeping. When
+ <command>kea-lfc</command> completes writing the outputfile, it moves it to this
+ file name. After <command>kea-lfc</command> finishes deleting the other files
+ (previous and input), it moves this file to the previous lease file. By moving the
+ files in this fashion, the <command>kea-lfc</command> and the DHCP server
processes can determine the correct file to use even if one of the
processes was interrupted before completing its task.
</simpara></listitem>
</itemizedlist>
</para>
- <para>There are several additional arguments mostly for debugging purposes.
- <command>-d</command> Sets the logging level to debug. <command>-v</command> and
- <command>-V</command> print out version stamps with <command>-V</command> providing
- a longer form. <command>-h</command> prints out the usage string.
+ <para>There are several additional arguments, mostly for debugging purposes.
+ <command>-d</command> sets the logging level to debug. <command>-v</command> and
+ <command>-V</command> print out version stamps, with <command>-V</command> providing
+ a longer form. <command>-h</command> prints out the usage string.
</para>
</section>