CONFIDENTIAL & RESTRICTED

Hi Everybody,

I'm facing a problem I don't manage to find an explanation.
I've got ian openshift pod with kafka 0.10.2.1 and a zookeeper 3.4.9. We have 
only one topic feeded by  a kafka connector running in another pod that sends 
around 21 messages per second.
For some reasons, for the moment, the topic has only one partition and there's 
only one broker. The 3 specific kafka connector topics has been well created 
except for the number of replication because of the number of broker.

In kafka logs we have often (around 15 times a day) this kind incident (kafka 
seems to loose hos connection to zookeeper):
[ 2018-10-02 06:56:03,404] WARN Client session timed out, have not heard from 
server in 4036ms for sessionid 0x165fc77d1ae002e 
(org.apache.zookeeper.ClientCnxn)
[2018-10-02 06:56:03,431] INFO Client session timed out, have not heard from 
server in 4036ms for sessionid 0x165fc77d1ae002e, closing socket connection and 
attempting reconnect (org.apache.zookeeper.ClientCnxn)
[2018-10-02 06:56:05,555] INFO Session establishment complete on server 
zookeeper-inval-cluster.default.svc.cluster.local/10.224.32.63:2181, sessionid 
= 0x165fc77d1ae002e, negotiated timeout = 6000 (org.apache.zookeeper.ClientCnxn)
[2018-10-02 09:44:58,831] WARN Client session timed out, have not heard from 
server in 7070ms for sessionid 0x165fc77d1ae002e 
(org.apache.zookeeper.ClientCnxn)
[2018-10-02 09:44:58,832] INFO Client session timed out, have not heard from 
server in 7070ms for sessionid 0x165fc77d1ae002e, closing socket connection and 
attempting reconnect (org.apache.zookeeper.ClientCnxn)
[2018-10-02 09:45:00,277] WARN Unable to reconnect to ZooKeeper service, 
session 0x165fc77d1ae002e has expired (org.apache.zookeeper.ClientCnxn)
[2018-10-02 09:45:00,277] INFO Unable to reconnect to ZooKeeper service, 
session 0x165fc77d1ae002e has expired, closing socket connection 
(org.apache.zookeeper.ClientCnxn)
[2018-10-02 09:45:01,844] INFO EventThread shut down for session: 
0x165fc77d1ae002e (org.apache.zookeeper.ClientCnxn)

On the zookeeper side, we have this logs:
2018-10-02 06:56:03,487 [myid:] - WARN  
[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn@357] - caught end of 
stream exception
EndOfStreamException: Unable to read additional data from client sessionid 
0x165fc77d1ae002e, likely client has closed socket
        at 
org.apache.zookeeper.server.NIOServerCnxn.doIO(NIOServerCnxn.java:228)
        at 
org.apache.zookeeper.server.NIOServerCnxnFactory.run(NIOServerCnxnFactory.java:203)
        at java.lang.Thread.run(Thread.java:748)
2018-10-02 06:56:03,515 [myid:] - INFO  
[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn@1008] - Closed socket 
connection for client /10.225.11.1:37874 which had sessionid 0x165fc77d1ae002e
2018-10-02 06:56:05,518 [myid:] - INFO  
[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@192] - Accepted 
socket connection from /10.225.11.1:34696
2018-10-02 06:56:05,545 [myid:] - INFO  
[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer@921] - Client 
attempting to renew session 0x165fc77d1ae002e at /10.225.11.1:34696
2018-10-02 06:56:05,545 [myid:] - INFO  
[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer@673] - Established 
session 0x165fc77d1ae002e with negotiated timeout 6000 for client 
/10.225.11.1:34696

Ok, the reconnection works fine and externally, for our application, everything 
is ok.
But, I wondering if it could be the sign of something under sized or something 
that's going wrong. I 'googled' the problem of course, but I didn't find any 
satisfying explanation or solution.
Is there a anybody who faced this kind of behaviour of for giving something to 
investigate further ?

Anyway, thank you very much for any help or suggestion.

Denis.



Reply via email to