SQL Statements for Controlling Replica Servers Setting  MASTER_HOST=’’  (that is, setting its value explicitly to an empty string) is  not  the same as not setting  MASTER_HOST  at all. Trying to set  MASTER_HOST  to an empty string fails with an error. MASTER_LOG_FILE , MASTER_LOG_POS The binary log file name, and the location in that file, at which the replication I/O thread begins reading from the source’s binary log the next time the thread starts. Specify these options if you are using binary log file position based replication.  MASTER_LOG_FILE  must include the numeric suffix of a specific binary log file that is available on the source server, for example,  MASTER_LOG_FILE=’binlog.000145’ . MASTER_LOG_POS  is the numeric position for the replica to start reading in that file.  MASTER_LOG_POS=4  represents the start of the events in a binary log file. If you specify either of  MASTER_LOG_FILE  or  MASTER_LOG_POS , you cannot specify  MASTER_AUTO_POSITION = 1 , which is for GTID- based replication. If neither of  MASTER_LOG_FILE  or  MASTER_LOG_POS  is specified, the replica uses the last coordinates of the  replication SQL thread before  CHANGE MASTER TO  was issued. This ensures that there is no discontinuity in replication, even if the replication SQL thread was late compared to the replication I/O thread. MASTER_PASSWORD The password for the replication user account to use for connecting to the replication source server. If you specify  MASTER_PASSWORD , MASTER_USER  is also required. The password used for a replication user account in a  CHANGE MASTER TO  statement is limited to 32 characters in length. Trying to use a password of more than 32 characters causes  CHANGE MASTER TO  to fail. MASTER_PORT The TCP/IP port number that the replica uses to connect to the replication source server. Note Replication cannot use Unix socket files. You must be able to connect to the replication source server using TCP/IP. If you specify  MASTER_HOST  or  MASTER_PORT , the replica assumes that the source server is different from before (even if the option value is the same as its current value.) In this case, the old values for the source’s binary log file name and position are considered no longer applicable, so if you do not specify  MASTER_LOG_FILE  and MASTER_LOG_POS  in the statement,  MASTER_LOG_FILE=’’  and MASTER_LOG_POS=4  are silently appended to it. MASTER_PUBLIC_KEY_PATH Enables RSA key pair-based password exchange by providing the path name to a file containing a replica-side copy of the public key required by the source. The file must be in PEM format. This option applies to replicas that authenticate with the  sha256_password or  caching_sha2_password  authentication plugin. (For 2751