I have a Percona mysql8.0.23 cluster, 1 master with 2 slaves on Ubuntu20, after I start io thread on slave, there are many unauthenticated user on the master, once I stop io thread, they are immediately gone, any ideas how can I troubleshoot? I set skip-name-resolve and there is no unknown ip access master, after I switch master to another machine, the problem still exists.
Switch off thread pool and the problem will go away
i.e. thread_handling = one-thread-per-connection
Why does slave connection to master result in unauthenticated user even though there is still a connection that is intact between master and slave. We can see this in the processlist. Why will it try to reconnect again and again. I have thread handling as pool of threads currently and avg connections to server is 100-200.