Unable to canonicalize address

[hatamiarash7]

Hey there

I have a little problem here with the single-node example. There is an error in Kafka pod :

[WARN] 2022-04-26 14:29:47,008 [main-SendThread(zookeeper.confluent.svc.cluster.local:2181)] org.apache.zookeeper.ClientCnxn run - Session 0x0 for sever zookeeper.confluent.svc.cluster.local:2181, Closing socket connection. Attempting reconnect except it is a SessionExpiredException.
java.lang.IllegalArgumentException: Unable to canonicalize address zookeeper.confluent.svc.cluster.local:2181 because it's not resolvable
        at org.apache.zookeeper.SaslServerPrincipal.getServerPrincipal(SaslServerPrincipal.java:78)
        at org.apache.zookeeper.SaslServerPrincipal.getServerPrincipal(SaslServerPrincipal.java:41)
        at org.apache.zookeeper.ClientCnxn$SendThread.startConnect(ClientCnxn.java:1161)
        at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1210)
[INFO] 2022-04-26 14:29:47,273 [main] kafka.zookeeper.ZooKeeperClient info - [ZooKeeperClient Kafka server] Closing.
[ERROR] 2022-04-26 14:29:48,112 [main-SendThread(zookeeper.confluent.svc.cluster.local:2181)] org.apache.zookeeper.client.StaticHostProvider resolve - Unable to resolve address: zookeeper.confluent.svc.cluster.local:2181
java.net.UnknownHostException: zookeeper.confluent.svc.cluster.local

Error messages :

Unable to canonicalize address zookeeper.confluent.svc.cluster.local:2181 because it's not resolvable
Unable to resolve address: zookeeper.confluent.svc.cluster.local:2181

I checked my zookeper ... it's good and works without a problem.

Also, check DNS using dnsutils :

$ kubectl -n default exec -it dnsutils -- nslookup zookeeper.confluent.svc.cluster.local

Server:         10.96.0.10
Address:        10.96.0.10#53

Name:   zookeeper.confluent.svc.cluster.local
Address: 192.168.0.111

What can I do?

[cjd9]

Had a similar error with my juberenetes setup. The problem was i set the ZOOKEEPER_HOST as zookeeper-service . when i renamed it to just zookeeper or any other name that does not contain a hyphen (-) , it finally worked. Maybe the kafka setup does not see zookeeper.confluent.svc.cluster.local as an valid host or url