Procédure de duplication du slave vers un autre expliquée dans le man de mysqldump

      ·   --master-data[=value]

          Use this option to dump a master replication server to produce a dump file that can be used to set up another server as a slave of the master. It causes the dump
          output to include a CHANGE MASTER TO statement that indicates the binary log coordinates (file name and position) of the dumped server. These are the master
          server coordinates from which the slave should start replicating after you load the dump file into the slave.

          If the option value is 2, the CHANGE MASTER TO statement is written as an SQL comment, and thus is informative only; it has no effect when the dump file is
          reloaded. If the option value is 1, the statement is not written as a comment and takes effect when the dump file is reloaded. If no option value is specified,
          the default value is 1.

          This option requires the RELOAD privilege and the binary log must be enabled.

          The --master-data option automatically turns off --lock-tables. It also turns on --lock-all-tables, unless --single-transaction also is specified, in which case,
          a global read lock is acquired only for a short time at the beginning of the dump (see the description for --single-transaction). In all cases, any action on
          logs happens at the exact moment of the dump.

          It is also possible to set up a slave by dumping an existing slave of the master. To do this, use the following procedure on the existing slave:

           1. Stop the slave´s SQL thread and get its current status:

                  mysql> STOP SLAVE SQL_THREAD;
                  mysql> SHOW SLAVE STATUS;

           2. From the output of the SHOW SLAVE STATUS statement, the binary log coordinates of the master server from which the new slave should start replicating are the
              values of the Relay_Master_Log_File and Exec_Master_Log_Pos fields. Denote those values as file_name and file_pos.

           3. Dump the slave server:

                  shell> mysqldump --master-data=2 --all-databases > dumpfile

           4. Restart the slave:

                  mysql> START SLAVE;

           5. On the new slave, load the dump file:

                  shell> mysql < dumpfile

           6. On the new slave, set the replication coordinates to those of the master server obtained earlier:

                  mysql> CHANGE MASTER TO
                      -> MASTER_LOG_FILE = ´file_name´, MASTER_LOG_POS = file_pos;

              The CHANGE MASTER TO statement might also need other parameters, such as MASTER_HOST to point the slave to the correct master server host. Add any such
              parameters as necessary.

Notes

Nommons les serveurs

  1. mysql51.master (server_id 1)
  2. mysql51.slave (server_id 2)
  3. mysql51.new.slave (server_id 3)

Mémorisation des infos de réplication depuis le slave

# Sur le slave
 
mysql> SHOW SLAVE STATUS;
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Slave_IO_State                   | Master_Host        | Master_User | Master_Port | Connect_Retry | Master_Log_File  | Read_Master_Log_Pos | Relay_Log_File          | Relay_Log_Pos | Relay_Master_Log_File | Slave_IO_Running | Slave_SQL_Running | Replicate_Do_DB | Replicate_Ignore_DB | Replicate_Do_Table | Replicate_Ignore_Table | Replicate_Wild_Do_Table | Replicate_Wild_Ignore_Table | Last_Errno | Last_Error | Skip_Counter | Exec_Master_Log_Pos | Relay_Log_Space | Until_Condition | Until_Log_File | Until_Log_Pos | Master_SSL_Allowed | Master_SSL_CA_File | Master_SSL_CA_Path | Master_SSL_Cert | Master_SSL_Cipher | Master_SSL_Key | Seconds_Behind_Master | Master_SSL_Verify_Server_Cert | Last_IO_Errno | Last_IO_Error | Last_SQL_Errno | Last_SQL_Error |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Waiting for master to send event | mysql51.xxxxxxxxxx | replication |        3306 |            60 | mysql-bin.000019 |           425272148 | PMP021-relay-bin.000054 |        951112 | mysql-bin.000019      | Yes              | Yes               |                 |                     |                    |                        |                         |                             |          0 |            |            0 |           425272148 |          951268 | None            |                |             0 | No                 |                    |                    |                 |                   |                |                     0 | No                            |             0 |               |              0 |                |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
1 row in set (0.00 sec)
 
mysql> SHOW SLAVE STATUS;
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Slave_IO_State                   | Master_Host        | Master_User | Master_Port | Connect_Retry | Master_Log_File  | Read_Master_Log_Pos | Relay_Log_File          | Relay_Log_Pos | Relay_Master_Log_File | Slave_IO_Running | Slave_SQL_Running | Replicate_Do_DB | Replicate_Ignore_DB | Replicate_Do_Table | Replicate_Ignore_Table | Replicate_Wild_Do_Table | Replicate_Wild_Ignore_Table | Last_Errno | Last_Error | Skip_Counter | Exec_Master_Log_Pos | Relay_Log_Space | Until_Condition | Until_Log_File | Until_Log_Pos | Master_SSL_Allowed | Master_SSL_CA_File | Master_SSL_CA_Path | Master_SSL_Cert | Master_SSL_Cipher | Master_SSL_Key | Seconds_Behind_Master | Master_SSL_Verify_Server_Cert | Last_IO_Errno | Last_IO_Error | Last_SQL_Errno | Last_SQL_Error |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Waiting for master to send event | mysql51.xxxxxxxxxx | replication |        3306 |            60 | mysql-bin.000019 |           425372539 | PMP021-relay-bin.000054 |       1051098 | mysql-bin.000019      | Yes              | Yes               |                 |                     |                    |                        |                         |                             |          0 |            |            0 |           425372134 |         1051659 | None            |                |             0 | No                 |                    |                    |                 |                   |                |                     0 | No                            |             0 |               |              0 |                |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
1 row in set (0.00 sec)
 
mysql> STOP SLAVE SQL_THREAD;
Query OK, 0 rows affected (0.06 sec)
 
mysql> SHOW SLAVE STATUS;
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Slave_IO_State                   | Master_Host        | Master_User | Master_Port | Connect_Retry | Master_Log_File  | Read_Master_Log_Pos | Relay_Log_File          | Relay_Log_Pos | Relay_Master_Log_File | Slave_IO_Running | Slave_SQL_Running | Replicate_Do_DB | Replicate_Ignore_DB | Replicate_Do_Table | Replicate_Ignore_Table | Replicate_Wild_Do_Table | Replicate_Wild_Ignore_Table | Last_Errno | Last_Error | Skip_Counter | Exec_Master_Log_Pos | Relay_Log_Space | Until_Condition | Until_Log_File | Until_Log_Pos | Master_SSL_Allowed | Master_SSL_CA_File | Master_SSL_CA_Path | Master_SSL_Cert | Master_SSL_Cipher | Master_SSL_Key | Seconds_Behind_Master | Master_SSL_Verify_Server_Cert | Last_IO_Errno | Last_IO_Error | Last_SQL_Errno | Last_SQL_Error |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Waiting for master to send event | mysql51.xxxxxxxxxx | replication |        3306 |            60 | mysql-bin.000019 |           425488485 | PMP021-relay-bin.000054 |       1135003 | mysql-bin.000019      | Yes              | No                |                 |                     |                    |                        |                         |                             |          0 |            |            0 |           425456039 |         1167605 | None            |                |             0 | No                 |                    |                    |                 |                   |                |                  NULL | No                            |             0 |               |              0 |                |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
1 row in set (0.00 sec)
 
mysql> SHOW SLAVE STATUS;
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Slave_IO_State                   | Master_Host        | Master_User | Master_Port | Connect_Retry | Master_Log_File  | Read_Master_Log_Pos | Relay_Log_File          | Relay_Log_Pos | Relay_Master_Log_File | Slave_IO_Running | Slave_SQL_Running | Replicate_Do_DB | Replicate_Ignore_DB | Replicate_Do_Table | Replicate_Ignore_Table | Replicate_Wild_Do_Table | Replicate_Wild_Ignore_Table | Last_Errno | Last_Error | Skip_Counter | Exec_Master_Log_Pos | Relay_Log_Space | Until_Condition | Until_Log_File | Until_Log_Pos | Master_SSL_Allowed | Master_SSL_CA_File | Master_SSL_CA_Path | Master_SSL_Cert | Master_SSL_Cipher | Master_SSL_Key | Seconds_Behind_Master | Master_SSL_Verify_Server_Cert | Last_IO_Errno | Last_IO_Error | Last_SQL_Errno | Last_SQL_Error |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Waiting for master to send event | mysql51.xxxxxxxxxx | replication |        3306 |            60 | mysql-bin.000019 |           425509662 | PMP021-relay-bin.000054 |       1135003 | mysql-bin.000019      | Yes              | No                |                 |                     |                    |                        |                         |                             |          0 |            |            0 |           425456039 |         1188782 | None            |                |             0 | No                 |                    |                    |                 |                   |                |                  NULL | No                            |             0 |               |              0 |                |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
1 row in set (0.00 sec)
 
# Donc nous allons reprendre la réplication depuis ces positions :
# Relay_Master_Log_File and Exec_Master_Log_Pos fields. Denote those values as file_name and file_pos.
# Relay_Master_Log_File : mysql-bin.000019
# Exec_Master_Log_Pos   : 425456039

Obligation d'activer les logs binaires sur le slave

mysqldump --host="mysql51.master" --user="monUserAvecDroits" --password="xxx" --all-databases --opt --routines --triggers --master-data=2 > mysql51.slave.sql
mysqldump: Error: Binlogging on server not active

Vous devez activez les logs binaires dans le fichier de configuration my.cnf avant de relancer le serveur slave.

SET GLOBAL log_bin = ON
#1238 - Variable 'log_bin' is a read only variable

/etc/mysql/my.cnf

# Enable binary logging. This is required for acting as a MASTER in a
# replication configuration. You also need the binary log if you need
# the ability to do point in time recovery from your latest backup.
log-bin=mysql-bin

# binary logging format - mixed recommended
binlog_format=mixed

Relancement du slave

# /etc/init.d/mysql restart

Relancement du new.slave et configuration en tant qu'esclave

# Vérification que le server_id est le bon
mysql> SHOW VARIABLES LIKE 'server_id';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id     | 3     |
+---------------+-------+
1 row in set (0.00 sec)
 
mysql> SHOW SLAVE STATUS;
Empty set (0.00 sec)
 
# Configuration de la position de reprise de cet esclave
mysql> CHANGE MASTER TO MASTER_HOST='mysql51.master', MASTER_PORT=3306, MASTER_USER='replication', MASTER_PASSWORD='xxx', MASTER_LOG_FILE='mysql-bin.000019', MASTER_LOG_POS=425456039;
Query OK, 0 rows affected (0.02 sec)
 
mysql> SHOW SLAVE STATUS;
+----------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Slave_IO_State | Master_Host        | Master_User | Master_Port | Connect_Retry | Master_Log_File  | Read_Master_Log_Pos | Relay_Log_File          | Relay_Log_Pos | Relay_Master_Log_File | Slave_IO_Running | Slave_SQL_Running | Replicate_Do_DB | Replicate_Ignore_DB | Replicate_Do_Table | Replicate_Ignore_Table | Replicate_Wild_Do_Table | Replicate_Wild_Ignore_Table | Last_Errno | Last_Error | Skip_Counter | Exec_Master_Log_Pos | Relay_Log_Space | Until_Condition | Until_Log_File | Until_Log_Pos | Master_SSL_Allowed | Master_SSL_CA_File | Master_SSL_CA_Path | Master_SSL_Cert | Master_SSL_Cipher | Master_SSL_Key | Seconds_Behind_Master | Master_SSL_Verify_Server_Cert | Last_IO_Errno | Last_IO_Error | Last_SQL_Errno | Last_SQL_Error |
+----------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
|                | mysql51.xxxxxxxxxx | replication |        3306 |            60 | mysql-bin.000019 |           425456039 | VMP035-relay-bin.000001 |             4 | mysql-bin.000019      | No               | No                |                 |                     |                    |                        |                         |                             |          0 |            |            0 |           425456039 |             106 | None            |                |             0 | No                 |                    |                    |                 |                   |                |                  NULL | No                            |             0 |               |              0 |                |
+----------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
1 row in set (0.00 sec)
 
# Activation/lancement de la réplication
mysql> START SLAVE;
Query OK, 0 rows affected (0.00 sec)
 
mysql> SHOW SLAVE STATUS;
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Slave_IO_State                   | Master_Host        | Master_User | Master_Port | Connect_Retry | Master_Log_File  | Read_Master_Log_Pos | Relay_Log_File          | Relay_Log_Pos | Relay_Master_Log_File | Slave_IO_Running | Slave_SQL_Running | Replicate_Do_DB | Replicate_Ignore_DB | Replicate_Do_Table | Replicate_Ignore_Table | Replicate_Wild_Do_Table | Replicate_Wild_Ignore_Table | Last_Errno | Last_Error | Skip_Counter | Exec_Master_Log_Pos | Relay_Log_Space | Until_Condition | Until_Log_File | Until_Log_Pos | Master_SSL_Allowed | Master_SSL_CA_File | Master_SSL_CA_Path | Master_SSL_Cert | Master_SSL_Cipher | Master_SSL_Key | Seconds_Behind_Master | Master_SSL_Verify_Server_Cert | Last_IO_Errno | Last_IO_Error | Last_SQL_Errno | Last_SQL_Error |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
| Waiting for master to send event | mysql51.xxxxxxxxxx | replication |        3306 |            60 | mysql-bin.000019 |           515983985 | VMP035-relay-bin.000002 |       4956004 | mysql-bin.000019      | Yes              | Yes               |                 |                     |                    |                        |                         |                             |          0 |            |            0 |           430411792 |        90528353 | None            |                |             0 | No                 |                    |                    |                 |                   |                |                  9401 | No                            |             0 |               |              0 |                |
+----------------------------------+--------------------+-------------+-------------+---------------+------------------+---------------------+-------------------------+---------------+-----------------------+------------------+-------------------+-----------------+---------------------+--------------------+------------------------+-------------------------+-----------------------------+------------+------------+--------------+---------------------+-----------------+-----------------+----------------+---------------+--------------------+--------------------+--------------------+-----------------+-------------------+----------------+-----------------------+-------------------------------+---------------+---------------+----------------+----------------+
1 row in set (0.00 sec)

Vous voila avec 2 slave mysql, qui se synchronisent depuis le même master (dont on a pas coupé les services). Enjoy !

Ressources