zookeper - Too many connections

[#1]

in the zoo logs we get the following warning :

we also get disconnecting issues from zookeper , is it possible to increase the "60" value?

what should be the ressolution for this ?

Too many connections from /10.54.23.11 - max is 60

from zoo log:

2018-06-12 06:31:56,901 - ERROR [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory$1@44] - Thread Thread[NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181,5,main] died
java.lang.OutOfMemoryError: Java heap space
        at java.nio.HeapByteBuffer.<init>(HeapByteBuffer.java:57)
        at java.nio.ByteBuffer.allocate(ByteBuffer.java:335)
        at org.apache.zookeeper.server.NIOServerCnxn.readLength(NIOServerCnxn.java:934)
        at org.apache.zookeeper.server.NIOServerCnxn.doIO(NIOServerCnxn.java:237)
        at org.apache.zookeeper.server.NIOServerCnxnFactory.run(NIOServerCnxnFactory.java:208)
        at java.lang.Thread.run(Thread.java:745

2018-06-12 06:18:16,687 - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn@1008] - Closed socket connection for client /10.164.46.204:52745 which had sessionid 0x163f299c1e20003
2018-06-12 06:18:16,687 - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner@108] - Revalidating client: 0x163f299c1e20003
2018-06-12 06:18:16,688 - INFO  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:ZooKeeperServer@617] - Established session 0x163f299c1e20003 with negotiated timeout 40000 for client /10.164.46.204:52835
2018-06-12 06:18:16,878 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:17,550 - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@197] - Accepted socket connection from /10.164.46.170:42523
2018-06-12 06:18:17,550 - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer@861] - Client attempting to renew session 0x163f299c1e20004 at /10.54.23.12:42523
2018-06-12 06:18:17,550 - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxn@1008] - Closed socket connection for client /10.164.46.170:42495 which had sessionid 0x163f299c1e20004
2018-06-12 06:18:17,551 - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:Learner@108] - Revalidating client: 0x163f299c1e20004
2018-06-12 06:18:17,552 - INFO  [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:ZooKeeperServer@617] - Established session 0x163f299c1e20004 with negotiated timeout 40000 for client /10.164.46.170:42523
2018-06-12 06:18:18,296 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:19,695 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:21,042 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:21,761 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:22,408 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:23,561 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
2018-06-12 06:18:24,192 - WARN  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@193] - Too many connections from /10.54.23.11 - max is 60
^C
[root@master01 zookeeper]# host 10.54.23.11
169.46.164.10.in-addr.arpa domain name pointer master01.sys76.com.

[#2]

in the first zoo log we can see also the following:

java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)
2018-06-12 18:35:01,856 - ERROR [CommitProcessor:1:NIOServerCnxn@178] - Unexpected Exception:
java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)
2018-06-12 18:35:01,857 - ERROR [CommitProcessor:1:NIOServerCnxn@178] - Unexpected Exception:
java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)
2018-06-12 18:35:01,857 - ERROR [CommitProcessor:1:NIOServerCnxn@178] - Unexpected Exception:
java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)
2018-06-12 18:35:01,857 - ERROR [CommitProcessor:1:NIOServerCnxn@178] - Unexpected Exception:
java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)
2018-06-12 18:35:01,857 - ERROR [CommitProcessor:1:NIOServerCnxn@178] - Unexpected Exception:
java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)
2018-06-12 18:35:01,857 - ERROR [CommitProcessor:1:NIOServerCnxn@178] - Unexpected Exception:
java.nio.channels.CancelledKeyException
        at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:73)
        at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:77)
        at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:151)
        at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1082)
        at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:391)
        at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:74)