Saikumar's Blog

Below is the error when I am trying to change the port of a MySQL server from 3306 to 3308. MySQL [ERROR] Can't start server: Bind on TCP/IP port: Permission denied [ERROR] Do you already have another mysqld server running on port: 3308? I have not seen any MySQL instance already running with port 3308 . After doing some troubleshooting i found that SELinux enabled on my server which is blocking this non-standard MySQL port 3308. root@slave.1 $ cat /etc/sysconfig/selinux # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: #     enforcing - SELinux security policy is enforced. #     permissive - SELinux prints warnings instead of enforcing. #     disabled - No SELinux policy is loaded. SELINUX=enforcing # SELINUXTYPE= can take one of three values: #     targeted - Targeted processes are protected, #     minimum - Modifica...

MySQL 5.7 GTID( Global Transactions Identifiers ) replication setup So far we are using binlog replication to sync data from master to slave. Here the problem comes. what if we want to do some slave topology changes. this includes much work to re-order slaves in a replication chain. More complex topology changes could require an admin to stop replication on the hosts involved.Now with the GTID configuratio,n we can easily move slaves in replication chain without stopping the replication. Here I'm setting up replication between a master and 4 slaves. master.0                  10.0.0.100 slave.1                    10.0.0.101 slave.2                    10.0.0.102 slave.3   ...