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<!doctype refentry PUBLIC "-//OASIS//DTD DocBook V4.1//EN" [ |
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<!-- Fill in your name for FIRSTNAME and SURNAME. --> |
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<!-- Please adjust the date whenever revising the manpage. --> |
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<!ENTITY dhdate "<date>June 20, 2007</date>"> |
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allowed: see man(7), man(1). --> |
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<!ENTITY dhsection "<manvolnum>8</manvolnum>"> |
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<!ENTITY dhucpackage "<refentrytitle>ganeti-watcher</refentrytitle>"> |
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<!ENTITY dhpackage "ganeti-watcher"> |
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<!ENTITY debian "<productname>Debian</productname>"> |
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<!ENTITY gnu "<acronym>GNU</acronym>"> |
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<!ENTITY gpl "&gnu; <acronym>GPL</acronym>"> |
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<!ENTITY footer SYSTEM "footer.sgml"> |
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]> |
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<refentry> |
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<refentryinfo> |
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<copyright> |
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<year>2007</year> |
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<holder>Google Inc.</holder> |
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</copyright> |
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&dhdate; |
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</refentryinfo> |
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<refmeta> |
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&dhucpackage; |
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&dhsection; |
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<refmiscinfo>ganeti 1.2</refmiscinfo> |
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</refmeta> |
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<refnamediv> |
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<refname>&dhpackage;</refname> |
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|
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<refpurpose>ganeti cluster watcher</refpurpose> |
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</refnamediv> |
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<refsynopsisdiv> |
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<cmdsynopsis> |
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<command>&dhpackage; </command> |
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|
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</cmdsynopsis> |
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</refsynopsisdiv> |
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<refsect1> |
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<title>DESCRIPTION</title> |
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|
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<para> |
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The <command>&dhpackage;</command> is a periodically run script |
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which is responsible for keeping the instances in the correct |
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status. |
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</para> |
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|
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<para> |
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Its function is to try to keep running all instances which are |
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marked as <emphasis>up</emphasis> in the configuration file, by |
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trying to start them a limited number of times. |
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</para> |
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|
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<para>In order to prevent piling up commands, all the |
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<emphasis>gnt-*</emphasis> commands executed by ganeti-watcher are |
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run with a timeout of 15 seconds. |
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</para> |
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|
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<para> |
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The command has a state file located at |
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<filename>/var/lib/ganeti/restart_state</filename> and a log |
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file at |
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<filename>/var/log/ganeti/watcher.log</filename>. Removal of |
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either file will not affect correct operation; the removal of |
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the state file will just cause the restart counters for the |
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instances to reset to zero. |
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</para> |
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|
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</refsect1> |
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|
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<refsect1> |
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<title>KNOWN BUGS</title> |
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|
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<para> |
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Due to the way we initialize DRBD peers, restarting a secondary |
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node for an instance will cause the DRBD endpoints on that node |
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to disappear, thus all instances which have that node as a |
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secondary will lose redundancy. The watcher does not detect this |
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situation. The workaround is to manually run |
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<command>gnt-instance activate-disks</command> for all the |
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affected instances. |
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</para> |
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</refsect1> |
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&footer; |
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</refentry> |
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Local variables: |
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mode: sgml |
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sgml-omittag:t |
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sgml-shorttag:t |
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sgml-minimize-attributes:nil |
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sgml-always-quote-attributes:t |
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sgml-indent-step:2 |
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sgml-indent-data:t |
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sgml-parent-document:nil |
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sgml-default-dtd-file:nil |
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sgml-exposed-tags:nil |
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sgml-local-catalogs:nil |
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sgml-local-ecat-files:nil |
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End: |
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--> |