Cluster Control don't import mysql replication
I tried to import four mysql node on Cluster Control.
My structure is like this :
A <-> B -> C -> D
mysql version : 5.7.23 Linux version : Ubuntu 18.04 LTS Cluster Control: Controller: 220.127.116.1125, Frontend: 18.104.22.16859
I get this error:
Adding existing cluster has failed. Found more than one writable node. Exactly one node must have 'read_only=OFF'. Correct the read_only settings and restart the job. Aborting.
Do you know how I can resolve this?
As stated in the error, ClusterControl allows only one node to accept write (read_only=OFF) in one given cluster during the import process for accurate topology detection. In your setup, it seems like A and B are writable. Simply set B to read_only=ON before the import process. You can change it back to read_only=OFF once the import process completes.
I'd like to emphasize here that despite supported by ClusterControl, if you are running with more than one writable master in a replication setup, you are exposed to a certain risks e.g, cluster recovery won't work accurately and load balancer integration for read/write splitting will also be a problem.
Please sign in to leave a comment.