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</o:shapelayout></xml><![endif]--></head><body lang=ES link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Pgpool triggers failover on this situations:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>With health_check functionality. Between intervals it checks the status of backends nodes and makes a failover if a node is detected as down.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>fail_over_on_backend_error: If this command is set to on, Initiates failover when reading/writing to the backend communication socket fails. If set to off, pgpool will report an error and disconnect the session.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Check these configurations.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>And start pgpool with –D option for descarting pgpool_status file.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Regards.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>De:</span></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> Anushka Weerakkodyge [mailto:anushkaw@ceylonit.com] <br><b>Enviado el:</b> miércoles, 22 de marzo de 2017 04:37 a. m.<br><b>Para:</b> Lazaro Garcia<br><b>CC:</b> pgpool-general@pgpool.net<br><b>Asunto:</b> Re: [pgpool-general: 5370] [pgpool] Streaming Replication - Identify Slave Node Status<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi Lazaro,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I tried failover command in pgpool and was able to stop the replication and make the master server a read only node when the standby is down. But I noticed that this procedure does not work always. Sometimes pgpool does not trigger failover mechanism when the standby node is down and log keeps showing <b>failed to make persistent db connection </b>message. Is there something I'm missing here ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>In the config file I turned on master_slave mode and load_balance mode.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Thanks,<o:p></o:p></p></div><div><p class=MsoNormal>Anushka<o:p></o:p></p></div></div></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Fri, Mar 17, 2017 at 5:10 AM, Anushka Weerakkodyge <<a href="mailto:anushkaw@ceylonit.com" target="_blank">anushkaw@ceylonit.com</a>> wrote:<o:p></o:p></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><p class=MsoNormal>Thank you! I will try this method definitely. By the way, what I really need is to fail the transaction when slave is down. Using this method I can identify the status of the slave node, then will try to make the master node read only until the slave comes online.<o:p></o:p></p></div><div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Thanks,<o:p></o:p></p></div><div><p class=MsoNormal>Anushka<o:p></o:p></p></div></div></div></div><div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Thu, Mar 16, 2017 at 6:36 PM, Lazaro Garcia <<a href="mailto:lazaro3487@gmail.com" target="_blank">lazaro3487@gmail.com</a>> wrote:<o:p></o:p></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>When slave goes down, pgpool detects that and triggers a failover, then the master remains active and the slave are marked as down state. On the failover_command of pgpool, you could execute a command that drop the slave from the master synchronous_standby_names and reload the configuration on the master. By this way new transactions can be executed on the master without checking the state of the slave because synchronous replication has been disabled.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If you recover the slave you can attach this server to master again an activate the synchronous replication.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>De:</span></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> <a href="mailto:pgpool-general-bounces@pgpool.net" target="_blank">pgpool-general-bounces@pgpool.net</a> [mailto:<a href="mailto:pgpool-general-bounces@pgpool.net" target="_blank">pgpool-general-bounces@pgpool.net</a>] <b>En nombre de </b>Anushka Weerakkodyge<br><b>Enviado el:</b> miércoles, 15 de marzo de 2017 05:37 p. m.<br><b>Para:</b> <a href="mailto:pgpool-general@pgpool.net" target="_blank">pgpool-general@pgpool.net</a><br><b>Asunto:</b> [pgpool-general: 5370] [pgpool] Streaming Replication - Identify Slave Node Status</span><o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hi all,<o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I have a synchronous streaming replication environment which is implemented using inbuilt replication mechanism in postgresql. There is a requirement that I need to fail the data modification transactions on master node if the slave node is down. (ie: transactions should commit when only both servers are up and running) <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Please let me know whether there is a way to identify slave node status and fail the transaction using pgpool ? <br clear=all><o:p></o:p></p><div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Thanks,<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Anushka<o:p></o:p></p></div></div></div></div></div></div></div></div></div></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>