Resolving MySQL Replication Issues: Enabling log‑slave‑updates and Granting Remote Access

There are three MySQL servers, A, B, and C. Server A replicates to B (master‑slave), and B is configured as the master for C. After adding log-slave-updates to B's my.cnf, B can sync from A, but C fails to connect to B, reporting

Last_IO_Error: error connecting to master '[email protected]:3307'

with error code 1130.

The error log on C shows repeated I/O connection failures and the same error code, indicating that the master (B) is rejecting the connection from C.

Testing the connection directly from C with the command mysql -u repl2 -h192.168.1.119 -P 3307 - returns

ERROR 1130 (HY000): Host '192.168.1.118' is not allowed to connect to this MySQL server

, confirming that B has not granted remote access to C.

To resolve the issue, on server B execute the following statements:

grant all on *.* to 'repl2'@'192.168.1.118' identified by 'mysqlslave';

flush privileges;

These commands grant the replication user repl2 permission to connect from C's IP address and reload the privilege tables.

After applying the grant, C can successfully connect to B and replication proceeds without further errors.