Can't do backups in K8s cluster

MongoDB Percona Backup for MongoDB
2

I did start from scratch, after found out the cluster was instable. Now installed everything in default namespace, both operator and cluster, and I don’t get above errors now anymore.

However, now if I want to login to Mongo, I am getting:

$ psmdb-db $ kubectl run -i --rm --tty percona-client ...

Error attaching, falling back to logs: unable to upgrade connection: container percona-client not found in pod percona-client_default

DNSHostNotFound: Failed to look up service "_mongodb._tcp.percona-db-psmdb-db-rs0.default.svc.cluster.local": Success

Altough this is not Backup related anymore I would be greatful for any hints. Description of psmdb returns ready states. I can login to the primary rs0-0 but not via the connection string referenced by percona helm charts without any replica index number.

    expose:
      enabled: true
      exposeType: ClusterIP

I switched expose.enabled: false and the rs0 service can be resolved now. Then I get:

{"t":{"$date":"2021-12-21T02:48:12.339Z"},"s":"I",  "c":"NETWORK",  "id":4333208, "ctx":"ReplicaSetMonitor-TaskExecutor","msg":"RSM host selection timeout","attr":{"replica
Set":"rs0","error":"FailedToSatisfyReadPreference: Could not find host matching read preference { mode: \"nearest\" } for set rs0"}}
Error: connect failed to replica set rs0/percona-db-psmdb-db-rs0-0.percona-db-psmdb-db-rs0.default.svc.cluster.local:27017,percona-db-psmdb-db-rs0-2.percona-db-psmdb-db-rs0
.default.svc.cluster.local:27017,percona-db-psmdb-db-rs0-1.percona-db-psmdb-db-rs0.default.svc.cluster.local:27017 :

I imagine I have to configure

replsets[0].configuration which is the custom config for mongod in replica set according to docs, how could one define ReadPreference in here to workaround the 4.4 bug I read about in a neighbouring thread. So I am looking at replication.localPingThresholdMs at https://docs.mongodb.com/manual/reference/configuration-options/ and Read Preference for Replica Sets https://docs.mongodb.com/manual/core/read-preference-mechanics/#std-label-replica-set-read-preference-behavior-member-selection because nearest option does not seem to work for me, even though primary should be default according to Percona docs.

One cannot help to wonder how these parameters set, would this happen to be correct parameters in values.yaml, i.e.:

replsets:
  - name: rs0
    size: 3
    configuration: 
       readPreference: primaryPreferred

Continuing this thread here: Could not find host matching read preference mode nearest for set rs0

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