Replication and Binary Logging Options and Variables System Variables Used on Replication Source Servers Note The following system variables are used for or by replication source servers: auto_increment_increment  and  auto_increment_offset  are intended for use with circular (source-to-source) replication, and can be used to control the operation of  AUTO_INCREMENT  columns. Both variables have global and session values, and each can assume an integer value between 1 and 65,535 inclusive. Setting the value of either of these two variables to 0 causes its value to be set to 1 instead. Attempting to set the value of either of these two variables to an integer greater than 65,535 or less than 0 causes its value to be set to 65,535 instead. Attempting to set the value of auto_increment_increment  or  auto_increment_offset  to a noninteger value produces an error, and the actual value of the variable remains unchanged. auto_increment_increment  is also supported for use with  NDB  tables. As of MySQL 8.0.18, setting the session value of this system variable is no longer a restricted operation. When Group Replication is started on a server, the value of  auto_increment_increment  is changed to the value of  group_replication_auto_increment_increment , which defaults to 7, and the value of  auto_increment_offset  is changed to the server ID. The changes are reverted when Group Replication is stopped. These changes are only made and reverted if  auto_increment_increment and  auto_increment_offset  each have their default value of 1. If their values have already been modified from the default, Group Replication does not alter them. From MySQL 8.0, the system variables are also not modified when Group Replication is in single-primary mode, where only one server writes. auto_increment_increment  and  auto_increment_offset  affect  AUTO_INCREMENT  column behavior as follows: 3497 • auto_increment_increment  controls the interval between successive column values. For example: • auto_increment_increment mysql>  SHOW VARIABLES LIKE ’auto_inc%’; +--------------------------+-------+ | Variable_name | Value | +--------------------------+-------+ | auto_increment_increment | 1 | | auto_increment_offset | 1 | +--------------------------+-------+ 2 rows in set (0.00 sec) Command-Line Format --auto-increment-increment=# System Variable auto_increment_increment Scope Global, Session Dynamic Yes SET_VAR  Hint Applies Yes Type Integer Default Value 1 Minimum Value 1 Maximum Value 65535