The document provides information about a company including its legal headquarters address in Milan, Italy and an operating unit address in Pomezia, Italy. It also lists contact phone numbers and faxes for both locations. The bottom of the document thanks the reader for their attention, suggesting it is the ending of a presentation.

1. partita iva e codice fiscale: 12938200156
c.c.i.a.a. milano n.1599095
registro imprese 12938200156
capitale sociale € 2.418.433,00 i.v.
direzione e sede legale
via campanini 6
20124 milano
tel: +39 02/66.732.1 – fax: +39 02/66.732.300
unità operativa
p.zza san benedetto da norcia 33
00071 pomezia (rm)
tel: +39 06/9826.9600 – fax: +39 06/9826.9680
Mirko Conte, Senior Architect
Oracle MySQL Day Roma, 11 Maggio 2017
Workshop tecnico:
MySQL Group Replication in action

2. 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

3. 3
Software: MySQL + applicazione
●
MySQL 5.7.18
●
MySQL Router 2.1.3
●
MySQL Shell 1.0.9
●
MySQL Enterprise Backup 4.1.0
●
MySQL Utilities 1.6.5
●
Apache 2.4.6 + PHP 5.4.16 (Oracle Linux 7.3)
●
Wordpress 4.7.4

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

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

6. 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

7. 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

8. 8
Configuriamo router e mysqlfailover
●
Configurazione router: /etc/mysqlrouter/mysqlrouter.conf
[routing:failover]
bind_address = 127.0.0.1:6446
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 --exec-
post-failover=script

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

10. 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,... --new-
master=conn-info --demote-master switchover

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

12. 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

13. 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

14. 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;

15. 15
Configuriamo router
●
/etc/mysqlrouter/mysqlrouter.conf
[routing:failover]
bind_address = 127.0.0.1:6446
destinations = mgr1,mgr2,mgr3
mode = read-write

16. 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

17. direzione e sede legale
via campanini 6
20124 milano
tel: +39 02/66.732.1 – fax: +39 02/66.732.300
unità operativa
p.zza san benedetto da norcia 33
00071 pomezia (rm)
tel: +39 06/9826.9600 – fax: +39 06/9826.9680
Grazie per l’attenzione!