Replication: Setting Auto Increment / Offset Variables
When using Replication it is important to avoid data collision. MySQL provides variables to avoid conflicts: auto_increment_increment and auto_increment_offset. By choosing non-conflicting values for these variables, servers will not have conflicts when inserting new rows into the same table.
For more details: https://dev.mysql.com/doc/refman/5.5/en/replication-options-master.html
To implement this strategy, add the following lines to the my.ini file on each replication server during One-Way Replication Setup or Daisy Chain Replication Setup (step 5). The my.ini file is typically located in C:\Program Files (x86)\MySQL\MySQL Server 5.5.
Change the following values:
auto-increment example if you have 3 servers:
Whenever you add or remove a server for daisy chain replication, you must also change the auto_increment_increment value on all servers. See Daisy Chain Replication: Adding a New Server.