I have 3 machines, let's call them Primary, Secondary 1 and Secondary 2. The Primary and Secondary 1 have an existing asynchronous replication that was set up manually that is already in production. Initially I was going to create a new replication from Primary to Secondary 2 using mysqlsh and InnoDB ReplicaSet, and leave the existing replication from Primary to Secondary 1 as is.
After installing mysql-shell and mysql-router to Primary and Secondary 2 from the MySQL repository, on the Primary I established a connection and attempted to configure the instance using the template:
dba.configureReplicaSetInstance('root@rs-1:3306', {clusterAdmin: "'rsadmin'@'rs-1%'"});
I got the below error message:
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Dba.configureReplicaSetInstance: This function is not available through a session to an instance belonging to an unmanaged asynchronous replication topology (RuntimeError)
>>
I thought, fair enough, I do have an existing replication set up, and therefore a managed and unmanaged replication topology cannot coexist. So logically, I thought I needed to bit the bullet and adopt the existing topology first.
So, I installed mysql-shell and mysql-router as well on Secondary 1 as well. I went back to Primary and connected to the instance using mysqlsh and issued the command from the template:
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A new replicaset with the topology visible from '<primary>:3306' will be created.
* Scanning replication topology...
** Scanning state of instance <primary>:3306
* Discovering async replication topology starting with db5:3306
Discovered topology:
- <primary>:3306: uuid=<some_UUID_number> read_only=no
* Checking configuration of discovered instances...
This instance reports its own address as <primary>:3306
<primary>:3306: Instance configuration is suitable.
* Checking discovered replication topology...
Dba.createReplicaSet: Target server is not part of an async replication topology (MYSQLSH 51151)
>>
I guess my observation is that Primary is either part of an async replication topology, or it isn't! I'm at a loss of what to do next. I'd be grateful if anyone can point me in the right direction.