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1. Identify the current master

2. For each broken slave, stop the Squirro cluster service:

   Code Block
   sudo systemctl stop sqclusterd

3. Ensure you have a running system with one cluster node.

4. At the master:

   Code Block

   mysql> RESET MASTER; Query OK, 0 rows affected (0.14 sec) mysql> FLUSH TABLES WITH READ LOCK; Query OK, 0 rows affected (0.00 sec) mysql> SHOW MASTER STATUS; +------------------+----------+--------------+------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +------------------+----------+--------------+------------------+ | mysql-bin.000001 | 12268 | | | +------------------+----------+--------------+------------------+ 1 row in set (0.00 sec) mysql> exit $ mkdir /var/lib/squirro/cluster/mysql/<date> $ mysqldump --host=127.0.0.1 --port=3306 --user=cluster --password=$(PASSWORD) --all-databases --master-data --single-transaction --result-file /var/lib/squirro/cluster/mysql/<date>/dump.db $ mysql -u root -p mysql> UNLOCK TABLES; mysql> exit $ cd /var/lib/squirro/cluster/mysql/<date>/ $ gzip dump.db $ scp dump.db.gz $(SSH_USER)@$(IP_SLAVE1):/tmp/ $ scp dump.db.gz $(SSH_USER)@$(IP_SLAVE2):/tmp/

5. On each slave:

   Code Block

   $ mkdir /var/lib/squirro/cluster/mysql/restore-<date> $ mv /tmp/dump.db.gz /var/lib/squirro/cluster/mysql/restore-<date> $ cd /var/lib/squirro/cluster/mysql/restore-<date> $ gunzip dump.db.gz $ mysql -u root -p mysql> stop slave; mysql> exit $ mysql --host=127.0.0.1 --port=3306 --user=cluster --password=$(PASSWORD) -e "source dump.db;" $ mysql -u root -p mysql> RESET SLAVE; mysql> change master to master_user='repl', master_password='PASSWORD'; mysql> show slave status\G; --> if master_host does not point to current master, e.g.: mysql> change master to master_host = "$(IP_MASTER)"; mysql> CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=12268; --> ensure that the position matches the value from SHOW MASTER STATUS; above mysql> START SLAVE; mysql> show slave status\G; --> ensure that Slave_IO_Running: Yes and Slave_SQL_Running: Yes $ sudo systemctl start sqclusterd $ monit summary