Workshop tecnico: MySQL Group Replication in action

Transcription

1 Workshop tecnico: MySQL Group Replication in action Mirko Conte, Senior Architect Oracle MySQL Day Roma, 11 Maggio 2017 direzione e sede legale via campanini milano tel: / fax: / unità operativa p.zza san benedetto da norcia pomezia (rm) tel: / fax: / partita iva e codice fiscale: c.c.i.a.a. milano n registro imprese capitale sociale ,00 i.v.

2 Agenda Dall'istanza singola al cluster: esplorazione di alcune tecniche di HA con le repliche, standard e GR a confronto. Ambiente: MySQL + applicazione demo Creiamo istanze slave con repliche standard e gestiamo il failover Trasformiamo le repliche in Group Replication Introduciamo InnoDB Cluster 2

3 Software: MySQL + applicazione MySQL MySQL Router MySQL Shell MySQL Enterprise Backup MySQL Utilities Apache PHP (Oracle Linux 7.3) Wordpress

4 Configurazioni: MySQL + applicazione Configurazioni /etc/my.cnf /var/www/html/wp-config.php 4

5 Architettura repliche standard App + Router mgr4 R mgr4 R M S M DB mgr1 mgr2 X mgr1 mgr2 S S mgr3 mgr3 5

6 Creiamo istanze slave con repliche standard (1/2) my.cnf report-host=host report-port=port server-id=id log-bin binlog-format=row enforce-gtid-consistency=on gtid-mode=on master-info-repository=table relay-log-info-repository=table log-slave-updates=on 6

7 Creiamo istanze slave con repliche standard (2/2) Provisioning dati con MEB: mysqlbackup --skip-binlog --backup-dir=path backup-and-apply-log mysqlbackup --backup-dir=path - force copy-back (implicito --login-path=client) meta/backup_gtid_executed.sql Read-only Configurazione replica: mysqlreplicate --master=conn-info --slave=conn-info --rpl-user=user:pwd 7

8 Configuriamo router e mysqlfailover Configurazione router: /etc/mysqlrouter/mysqlrouter.conf [routing:failover] bind_address = :6446 destinations = host1:port,host2:port mode = read-write mysqlfailover mysqlfailover --master=conn-info --slaves=conn-info,conn-info,... --candidates=conn-info,... --daemon=start --failover-mode=elect --log=/var/log/mysqlfailover.log --pidfile=/var/run/mysqlfailover --execpost-failover=script 8

9 Failover Monitoraggio failover: /var/log/mysqlfailover.log /var/log/mysqlrouter/mysqlrouter.log 9

10 Post failover: ricostruire la replica Stop mysqlfailover: pkill -9 mysqlfailover rm -f /var/run/mysqlfailover SET sql_log_bin=0; DROP TABLE IF EXISTS mysql.failover_console; Tentiamo il riallineamento del nodo principale tramite replica dal master: mysqlreplicate --master=conn-info --slave=conn-info rpl-user=user:pwd Invertiamo i ruoli con mysqlrpladmin, in caso di errant transactions il nodo dovrà essere allineato con backup e restore: mysqlrpladmin --master=conn-info slaves=conn-info,conn-info,... --newmaster=conn-info --demote-master switchover 10

11 Architettura Group Replication App + Router mgr4 R mgr4 R DB mgr1 mgr2 mgr3 Xmgr1 mgr2 mgr3 11

12 Requisiti della Group Replication Requisiti e limitazioni: Richiesto storage engine InnoDB Richieste primary keys esplicite Network Performance e Ipv4 Binary log formato ROW (non supportato checksum) Transaction savepoints non supportati Non adatto a very large transactions Con multi-primary: gap locks, table locks, named locks, DDL + DML concorrenti, foreign keys con cascading constraints, possibilità di abort al commit per optimistic execution 12

13 Convertiamo in Group Replication (1/2) my.cnf binlog_checksum=none transaction_write_set_extraction=xxhash64 disabled_storage_engines=myisam,blackhole,federated,csv,archive loose-group_replication_group_name="uuid" loose-group_replication_start_on_boot=off loose-group_replication_local_address="host:port" loose-group_replication_group_seeds="host:port,host:port,host:port" loose-group_replication_bootstrap_group=off loose-group_replication_single_primary_mode=off Nota: opzione disabled_storage_engines unica non dinamica, non necessaria 13

14 Convertiamo in Group Replication (2/2) Configuriamo i nodi: INSTALL PLUGIN group_replication SONAME 'group_replication.so'; CREATE USER user IDENTIFIED BY 'password'; GRANT REPLICATION SLAVE ON *.* TO user; CHANGE MASTER TO MASTER_USER='user', MASTER_PASSWORD='password' FOR CHANNEL 'group_replication_recovery'; Attiviamo la GR sul primo nodo: SET GLOBAL group_replication_bootstrap_group=on; START GROUP_REPLICATION; SET GLOBAL group_replication_bootstrap_group=off; Altri nodi: START GROUP_REPLICATION; 14

15 Configuriamo router /etc/mysqlrouter/mysqlrouter.conf [routing:failover] bind_address = :6446 destinations = mgr1,mgr2,mgr3 mode = read-write 15

16 Convertiamo in InnoDB Cluster Convertiamo GR a InnoDB Cluster: mysqlsh --uri root:password@host var cluster = dba.createcluster('clustername', {adoptfromgr: true}) mysqlrouter --bootstrap root:password@host --user=mysqlrouter -force Passiamo da replica standard a InnoDB Cluster: dba.configurelocalinstance('root@localhost:3306', {password:'password', mycnfpath:'/etc/my.cnf'}) var cluster=dba.createcluster('clustername') cluster.addinstance('root:password@host') mysqlrouter --bootstrap root:password@host --user=mysqlrouter -force 16

17 Grazie per l attenzione! direzione e sede legale via campanini milano tel: / fax: / unità operativa p.zza san benedetto da norcia pomezia (rm) tel: / fax: /