From 208f82b6199c6a17fe4f9ba0e12db2b9bf69e740 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Javier=20Jaramago=20Fern=C3=A1ndez?= Date: Thu, 10 Dec 2020 10:26:11 +0000 Subject: [PATCH] Fixed the complete removal of servers that just belong to 'reader_hostgroup' when 'writer_is_also_reader=2' --- lib/MySQL_HostGroups_Manager.cpp | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/lib/MySQL_HostGroups_Manager.cpp b/lib/MySQL_HostGroups_Manager.cpp index b78558547..09f197a0d 100644 --- a/lib/MySQL_HostGroups_Manager.cpp +++ b/lib/MySQL_HostGroups_Manager.cpp @@ -5560,11 +5560,16 @@ void MySQL_HostGroups_Manager::converge_galera_config(int _writer_hostgroup) { } } if (num_backup_writers) { // there are backup writers, only these will be used as readers - q=(char *)"DELETE FROM mysql_servers_incoming WHERE hostgroup_id=%d"; - query=(char *)malloc(strlen(q) + 128); - sprintf(query,q, info->reader_hostgroup); + // just delete the readers which are right now part of the writer hostgroup, preserving + // any current reader which is only in the reader hostgroup. This is because if a server + // is only part of the reader hostgroup at this point, means that it's there because of a + // reason beyond ProxySQL control, e.g. having READ_ONLY=1. + q=(char*)"DELETE FROM mysql_servers_incoming where hostgroup_id=%d and (hostname,port) in (SELECT hostname,port FROM mysql_servers_incoming WHERE hostgroup_id=%d)"; + query=(char*)malloc(strlen(q) + 128); + sprintf(query, q, info->reader_hostgroup, info->writer_hostgroup); mydb->execute(query); free(query); + q=(char *)"INSERT OR IGNORE INTO mysql_servers_incoming (hostgroup_id,hostname,port,gtid_port,status,weight,compression,max_connections,max_replication_lag,use_ssl,max_latency_ms,comment) SELECT %d,hostname,port,gtid_port,status,weight,compression,max_connections,max_replication_lag,use_ssl,max_latency_ms,comment FROM mysql_servers_incoming WHERE hostgroup_id=%d"; query=(char *)malloc(strlen(q) + 128); sprintf(query,q, info->reader_hostgroup, info->backup_writer_hostgroup);