Re: [Pgpool-general] difference between master and primary node in streaming mode
Streaming replication mode is a master-slave replication system, this method allows to have a copy of the database, in a different database server. The purpose of this, is continues with the database service with slaves, in case of failures in the master or primary server. Streaming replication can be combined with host standby, allowing read queries in the slave or standby servers, for balancing the load between the servers. Regards. -Mensaje original- De: pgpool-general-boun...@pgfoundry.org [mailto:pgpool-general-boun...@pgfoundry.org] En nombre de Jeff Frost Enviado el: miércoles, 05 de octubre de 2011 02:39 Para: pgpool-general@pgfoundry.org Asunto: [Pgpool-general] difference between master and primary node in streaming mode What's the difference between the master and primary node in streaming replication mode? Occasionally, in my testing, I see this: Oct 5 11:36:08 31214-1-807393 pgpool[28871]: find_primary_node_repeatedly: waiting for finding a primary node Oct 5 11:36:08 31214-1-807393 pgpool[28871]: last message repeated 10 times Oct 5 11:36:08 31214-1-807393 pgpool[28871]: find_primary_node: 0 node is standby Oct 5 11:36:08 31214-1-807393 pgpool[28871]: last message repeated 10 times Oct 5 11:36:08 31214-1-807393 pgpool[28871]: find_primary_node: primary node id is 1 Oct 5 11:36:08 31214-1-807393 pgpool[28871]: failover: set new primary node: 1 Oct 5 11:36:08 31214-1-807393 pgpool[28871]: failover: set new master node: 0 Note that the primary and master are different. I understand that the primary node is considered whichever node is not in recovery mode, but what is the master? -- Jeff Frost j...@pgexperts.com CTO, PostgreSQL Experts, Inc. Phone: 1-888-PG-EXPRT x506 FAX: 415-762-5122 http://www.pgexperts.com/ ___ Pgpool-general mailing list Pgpool-general@pgfoundry.org http://pgfoundry.org/mailman/listinfo/pgpool-general ___ Pgpool-general mailing list Pgpool-general@pgfoundry.org http://pgfoundry.org/mailman/listinfo/pgpool-general
Re: [Pgpool-general] difference between master and primary node in streaming mode
What's the difference between the master and primary node in streaming replication mode? Occasionally, in my testing, I see this: Oct 5 11:36:08 31214-1-807393 pgpool[28871]: find_primary_node_repeatedly: waiting for finding a primary node Oct 5 11:36:08 31214-1-807393 pgpool[28871]: last message repeated 10 times Oct 5 11:36:08 31214-1-807393 pgpool[28871]: find_primary_node: 0 node is standby Oct 5 11:36:08 31214-1-807393 pgpool[28871]: last message repeated 10 times Oct 5 11:36:08 31214-1-807393 pgpool[28871]: find_primary_node: primary node id is 1 Oct 5 11:36:08 31214-1-807393 pgpool[28871]: failover: set new primary node: 1 Oct 5 11:36:08 31214-1-807393 pgpool[28871]: failover: set new master node: 0 Note that the primary and master are different. I understand that the primary node is considered whichever node is not in recovery mode, but what is the master? The master node is the node which is alive and has the least node id. Not important in streaming replication mode(important in pgpool-II native replication mode, though). -- Tatsuo Ishii SRA OSS, Inc. Japan English: http://www.sraoss.co.jp/index_en.php Japanese: http://www.sraoss.co.jp ___ Pgpool-general mailing list Pgpool-general@pgfoundry.org http://pgfoundry.org/mailman/listinfo/pgpool-general
Re: [Pgpool-general] difference between master and primary node in streaming mode
On 10/05/11 16:09, Tatsuo Ishii wrote: What's the difference between the master and primary node in streaming replication mode? The master node is the node which is alive and has the least node id. Not important in streaming replication mode(important in pgpool-II native replication mode, though). -- Ah! Thank you! So, Is it safe to assume that in streaming replication mode, the %H special value for follow_master_command will actually be the hostname of the new primary node and not the hostname of the new master node? -- Jeff Frost j...@pgexperts.com CTO, PostgreSQL Experts, Inc. Phone: 1-888-PG-EXPRT x506 FAX: 415-762-5122 http://www.pgexperts.com/ ___ Pgpool-general mailing list Pgpool-general@pgfoundry.org http://pgfoundry.org/mailman/listinfo/pgpool-general
