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Not able to start zookeeper after CDH 4.1 Installation

Rising Star

I created 3 VMs called nn1, nn2, and jt1 and assigned static IP addresses to each. I ensured that all VMs are able to ping one another.

I also edited the hosts file on each VM to that nn1, nn2 and jt1 have entries against their IP addresses.


Then I installed jdk-6u45-linux-x64-rpm.bin on each of the VMs.


Next i executed this command on all 3 VMs


wget http://
cp cloudera-cdh4.repo /etc/yum.repos.d/
rpm --import


Then I installed the following on all 3 nodes


yum install hadoop-hdfs-namenode
yum install hadoop-hdfs-journalnode
yum install zookeeper-server


I installed this only on nn1 and nn2


yum install hadoop-hdfs-zkfc


Finally I edit the /etc/zookeper/conf/zoo.cfg and added 3 lines (on all 3 machines)




I also executed this command on each machine


firewall-cmd --zone=dmz --add-port=2888/tcp --permanent
firewall-cmd --zone=dmz --add-port=3888/tcp --permanent
firewall-cmd --reload


But I keep seeing these errors in the /var/log/zookeeper/zookeeper.log file of each machine


WARN [WorkerSender[myid=1]:QuorumCnxManager@368] - Cannot open channel to 3 at election address jt1/ No route to host at Method)


Can you please tell me if I have left out a step in my cdh 4.1 configuration and also how can I troubleshoot this.

Also... I can see the word "WARN" here so is it just a warning? how can I know if my zookeeper is running successfully (perhaps with some warnings).


Can you please help me and sorry if this is FAQ.


Expert Contributor

ah you are on a different version of netcat




nc 3888



View solution in original post


Expert Contributor


no route to host suggests you are getting blocked still, using ping as a network test usually isn't sufficient as it uses the ICMP protocol and doesn't have a port per se.


a better test would be:


nc -z 3888 

Rising Star

for me it says 


nc: invalid option -- 'z'

Ncat: try --help or main(1) ncat for more information, usage options and help.


Expert Contributor

ah you are on a different version of netcat




nc 3888



Rising Star

I was able to successfully nc into all machines except one.


I went and re-issued these commands on that machine and that resolved the issue.


servicectl stop firewalld.service

servicectl disable firewalld.service


Thank you so much!!!!!

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