Hello everyone,
I have the following scenario with a "Single-Primary" InnoDB Cluster running with 3 nodes all of them recently upgraded from MySQL 8.0.27 to 8.0.40
One of the nodes "hostname1" is a Secondary node but I have the following warning on it: "WARNING: Instance is NOT a PRIMARY but super_read_only option is OFF."
Because I had no logs enabled at the time I can't find out when/how/why the cluster became into this state and I was wondering if this has ever happened to anyone else ? If so, any chance you know what happened and how this can be prevented from happening again?
Also, is it possible that this issue has something to do with the recent upgrade of the mysql versions that allow a Single-Primary cluster to have 2 nodes in R/W mode (when one of them in a Secondary)?
Cluster status:
{
"clusterName": "myCluster",
"defaultReplicaSet": {
"name": "default",
"primary": "hostname3:<port>",
"ssl": "REQUIRED",
"status": "OK",
"statusText": "Cluster is ONLINE and can tolerate up to ONE failure.",
"topology": {
"hostname1:<port>": {
"address": "hostname1:<port>",
"instanceErrors": [
"WARNING: Instance is NOT a PRIMARY but super_read_only option is OFF."
],
"memberRole": "SECONDARY",
"mode": "R/W",
"readReplicas": {},
"replicationLag": "applier_queue_applied",
"role": "HA",
"status": "ONLINE",
"version": "8.0.40"
},
"hostname2:<port>": {
"address": "hostname2:<port>",
"memberRole": "SECONDARY",
"mode": "R/O",
"readReplicas": {},
"replicationLag": "applier_queue_applied",
"role": "HA",
"status": "ONLINE",
"version": "8.0.40"
},
"hostname3:<port>": {
"address": "hostname3:<port>",
"memberRole": "PRIMARY",
"mode": "R/W",
"readReplicas": {},
"replicationLag": "applier_queue_applied",
"role": "HA",
"status": "ONLINE",
"version": "8.0.40"
}
},
"topologyMode": "Single-Primary"
},
"groupInformationSourceMember": "hostname3:<port>"
}