<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body><div><div style="font-family: Calibri,sans-serif; font-size: 11pt;">That makes sense. I'll look into the "failover script" in detail now.<br><br>I think I'd manually manage bringing back up the nodes that went down.<br><br>Many thanks Tatsuo,<br>Steven</div></div><div dir="ltr"><hr><span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">From: </span><span style="font-family: Calibri,sans-serif; font-size: 11pt;"><a href="mailto:ishii@postgresql.org">Tatsuo Ishii</a></span><br><span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">Sent: </span><span style="font-family: Calibri,sans-serif; font-size: 11pt;">03/01/2016 10:49</span><br><span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">To: </span><span style="font-family: Calibri,sans-serif; font-size: 11pt;"><a href="mailto:steven@livz.org">steven@livz.org</a></span><br><span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">Cc: </span><span style="font-family: Calibri,sans-serif; font-size: 11pt;"><a href="mailto:pgpool-general@pgpool.net">pgpool-general@pgpool.net</a></span><br><span style="font-family: Calibri,sans-serif; font-size: 11pt; font-weight: bold;">Subject: </span><span style="font-family: Calibri,sans-serif; font-size: 11pt;">Re: [pgpool-general: 4279] Is Master/Slave promotion supported ornot?</span><br><br></div>> Hi all. I am slightly confused. I seem to have read two relatively recent,<br>> but possibly contradictory statements on master/slave (using SR) promotion<br>> using pgpool.<br>> <br>> The first at [1] states "pcp_promote_node just changes the status in<br>> pgpool-II and does nothing with PostgreSQL server side."<br>> <br>> The second at [2] states "HOW TO PROMOTE THE SLAVE. This will happen<br>> automatically with pgpool. The manual process is described here for good<br>> measure but we should not have to use it."<br>> <br>> On one hand in [1] I am reading that only *within* PGPool do you see the<br>> master/slave promotion happening (which is indeed something i see when i<br>> run show pool_nodes) with no promotion of the actual Postgres slave.<br>> <br>> However the blog at [2] suggests it all happens as part of the PGPool<br>> process and your Postgres Slave will become the new Master automatically<br>> (although to put back the original master is clearly a manual process).<br>> <br>> Can someone clear this up please :-) I really just want the Slave to become<br>> the new Master and PGPool knows this but the backend servers don't and I'm<br>> slightly at a loss as how to tell them. Maybe I am missing a config setting.<br><br>Probably what you want actually includes two things:<br><br>1) Promote one of slaves<br><br>2) Let the downed master (old master) become a new slave following the<br> new master (that was promoted in #1)<br><br>For #1, create a "failover script".<br>See http://www.pgpool.net/pgpool-web/contrib_docs/simple_sr_setting2_3.3/index.html<br>for an example.<br><br>For #2, you really ought to think it should happen automatically or<br>not. If the cause that old master went down was a hardware failure,<br>you have to fix it first. In this case automated process is impossible<br>or dangerous. If you are sure it should happen automatically, you<br>could create your own "follow master command".<br><br>Best regards,<br>--<br>Tatsuo Ishii<br>SRA OSS, Inc. Japan<br>English: http://www.sraoss.co.jp/index_en.php<br>Japanese:http://www.sraoss.co.jp<br><br>> Much Appreciated,<br>> steven<br>> <br>> [1] http://www.sraoss.jp/pipermail/pgpool-general/2015-January/003464.html<br>> <br>> [2] http://www.accustack.com/postgresql-replication-pgpool-ii/<br></body></html>