https://pgpool.net/mediawiki/index.php?action=history&feed=atom&title=watchdog_feature_enhancement 2026-05-03T23:59:20Z Revision history for this page on the wiki MediaWiki 1.43.3 https://pgpool.net/mediawiki/index.php?title=watchdog_feature_enhancement&diff=1016&oldid=prev 2015-06-15T19:16:17Z

<p><span class="autocomment">What is required by the watchdog?</span></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 19:16, 15 June 2015</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l32">Line 32:</td> <td colspan="2" class="diff-lineno">Line 32:</td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [pgpool-general: 3228] Split brain or using 3 nodes ?</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [pgpool-general: 3228] Split brain or using 3 nodes ?</div></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [pgpool-general: 3728] Re: pgpool-general Digest, Vol 43, Issue 17</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [pgpool-general: 3728] Re: pgpool-general Digest, Vol 43, Issue 17</div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==== '''Design proposal for enhanced watchdog''' ====</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==== Terminologies used below ====</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">'''Cluster''':  Cluster is the logical entity which contains all the pgpool-II server nodes connected by pgpool-II watchdog.</ins></div></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====What is required by the watchdog?====</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====What is required by the watchdog?====</div></td></tr> </table>

Usama https://pgpool.net/mediawiki/index.php?title=watchdog_feature_enhancement&diff=1015&oldid=prev 2015-06-15T19:10:40Z

<p><span class="autocomment">Some pgpool-II general mailing list threads related to watchdog</span></p> <a href="https://pgpool.net/mediawiki/index.php?title=watchdog_feature_enhancement&amp;diff=1015&amp;oldid=1014">Show changes</a>

Usama https://pgpool.net/mediawiki/index.php?title=watchdog_feature_enhancement&diff=1014&oldid=prev 2015-06-15T15:30:34Z

<p><span class="autocomment">Some pgpool-II general mailing list threads related to watchdog</span></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:30, 15 June 2015</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l28">Line 28:</td> <td colspan="2" class="diff-lineno">Line 28:</td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: 4-- Wants watchdog on cloud and active-active watchdog configurations</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: 4-- Wants watchdog on cloud and active-active watchdog configurations</div></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td></tr> <tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>'''<del style="font-weight: bold; text-decoration: none;">:</del>Still open Issues'''</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">:</ins>'''Still open Issues'''</div></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: -- [pgpool-general: 3724] delegate ip lost</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: -- [pgpool-general: 3724] delegate ip lost</div></td></tr> <tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l34">Line 34:</td> <td colspan="2" class="diff-lineno">Line 34:</td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: -- [pgpool-general: 3228] Split brain or using 3 nodes ?</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: -- [pgpool-general: 3228] Split brain or using 3 nodes ?</div></td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: -- [pgpool-general: 3728] Re: pgpool-general Digest, Vol 43, Issue 17</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>: -- [pgpool-general: 3728] Re: pgpool-general Digest, Vol 43, Issue 17</div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">What is required by the watchdog?</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">---------------------------------------------------</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">The main purpose of the watchdog in pgpool-II is to provide high availability, For this purpose the watchdog is required to ensure following.</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">-- Ensure only healthy nodes are part of the cluster</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">-- Ensure only authorized nodes can become the member of the cluster</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">-- Ensure only one pgpool-II node is a designated master node at any time</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">-- Provide the automatic recovery mechanism when possible when some problem occurs</ins></div></td></tr> </table>

Usama https://pgpool.net/mediawiki/index.php?title=watchdog_feature_enhancement&diff=1013&oldid=prev 2015-06-15T15:26:23Z

<p>Created page with &quot;==== What&#039;s driving this enhancement ==== :Watchdog is a very important feature of pgpool-II as it is used to eliminate the single point of failure and provide HA. But there are ...&quot;</p> <p><b>New page</b></p><div>==== What&#039;s driving this enhancement ====<br /> :Watchdog is a very important feature of pgpool-II as it is used to eliminate the single point of failure and provide HA. But there are few feature requests and bugs in the existing watchdog that require little more than a simple code fix, and requires the complete revisit of its core architecture. So this enhancement of watchdog is aimed at providing the stability and robustness to the existing pgpool-II watchdog with some new cool features.<br /> <br /> == Some pgpool-II general mailing list threads related to watchdog ==<br /> <br /> : -- [pgpool-general: 3724] delegate ip lost<br /> : -- [pgpool-II 0000135]: Delegate IP does not get up on Standby upon Active gets disconnected (same in ppgool-general: 3736)<br /> : -- Split-brain scenario due to network partitioning <br /> : -- [ppgool-general: 3595] Watchdog issue.<br /> : -- [pgpool-general: 3443] watchdog on cloud<br /> : -- [pgpool-general: 3126] watchdog voting<br /> : -- [pgpool-general: 2985] Re: Connections stuck in CLOSE_WAIT, again<br /> : -- [pgpool-general: 2949] Re: pgpool 3.3.3 watchdog problem<br /> : -- [pgpool-general: 2797] pcp_watchdog_info parameters<br /> : -- [pgpool-general: 2768] timeout Watchdog<br /> : -- [pgpool-general: 2427] watchdog quorum<br /> : -- [pgpool-general: 2418] Re: watchdog: different statuses on different pgpool nodes.<br /> : -- [pgpool-general: 3772] Race condition for VIP assignment<br /> : -- Lots of question on suid or root privileges are required ([pgpool-general: 3323] Re: Watchdog - ifconfig up failed)<br /> : -- User wants ACTIVE-ACTIVE pgpool-II configuration and miscellaneous comments on the difficulty in configuration of watchdog<br /> <br /> :&#039;&#039;&#039;Summary&#039;&#039;&#039; <br /> <br /> :Analyzing above pgpool-II community threads related to watchdog, It comes down to four main areas where current pgpool-II watchdog requires some enhancements.<br /> : 1-- Related to Virtual IP assignments and handling the case of lost of VIP<br /> : 2-- Split-brain scenario, recovery from it and watchdog quorum<br /> : 3-- Users run into misconfigured watchdog situations very often.<br /> : 4-- Wants watchdog on cloud and active-active watchdog configurations<br /> <br /> &#039;&#039;&#039;:Still open Issues&#039;&#039;&#039;<br /> <br /> : -- [pgpool-general: 3724] delegate ip lost<br /> : -- [pgpool-general: 3772] Race condition for VIP assignment<br /> : -- [pgpool-general: 3228] Split brain or using 3 nodes ?<br /> : -- [pgpool-general: 3728] Re: pgpool-general Digest, Vol 43, Issue 17</div>

Usama