question Clean up unreachable zookeeper server in Archives of Support Questions (Read Only)

Clean up unreachable zookeeper server

a_gulshani — Tue, 03 Oct 2017 11:09:23 GMT

Hi all!
We had an HDF cluster with 6 servers. We accedentally removed servers for OS reinstallation where we had zookeeper servers installed. Now the zookeeper is broken and we cannot use nifi either.

Can you please help us remove the remainings of old servers from zookeeper's configurations and move it to remaining 3 servers.

thanks in advance!

Re: Clean up unreachable zookeeper server

bkosaraju — Tue, 03 Oct 2017 12:55:25 GMT

Hi @Gulshan Agivetova,

To remove the zookeeper service from the cluster, the simple method is to use the REST API and have the zookeeper service restarted.

Command to remove the service:

curl -i -u admin:admin -H "X-Requested-By: ambari" -X DELETE http://<ambari-Server>:<ambari-port>/api/v1/clusters/<cluster-name>/hosts/<fully_qualified_host_name(to_be_removed)>/host_components/ZOOKEEPER_SERVER

I presume, at least other hosts are alive in zookeeper quorum(to retain the data).

On the other Note, it is always good to have odd number of zookeeper nodes in cluster, hence you can add a new zookeeper server by doing

Go to Hosts in Ambari -> select the new node to be installed with zookeeper Server -> click on Components Add+ -> select Zookeeper Server and install.(same for ZOOKEEPER_CLIENT)

Hope this helps!

Re: Clean up unreachable zookeeper server

bkosaraju — Tue, 03 Oct 2017 12:55:28 GMT

Hi @Gulshan Agivetova,

To remove the zookeeper service from the cluster, the simple method is to use the REST API and have the zookeeper service restarted.

Command to remove the service:

curl -i -u admin:admin -H "X-Requested-By: ambari" -X DELETE http://<ambari-Server>:<ambari-port>/api/v1/clusters/<cluster-name>/hosts/<fully_qualified_host_name(to_be_removed)>/host_components/ZOOKEEPER_SERVER

I presume, at least other hosts are alive in zookeeper quorum(to retain the data).

On the other Note, it is always good to have odd number of zookeeper nodes in cluster, hence you can add a new zookeeper server by doing

Go to Hosts in Ambari -> select the new node to be installed with zookeeper Server -> click on Components Add+ -> select Zookeeper Server and install.(same for ZOOKEEPER_CLIENT)

Hope this helps!

Re: Clean up unreachable zookeeper server

a_gulshani — Tue, 03 Oct 2017 13:51:56 GMT

Hi, @bkosaraju!!

Thank you very much!

It helped!

We managed to remove zookeeper server from unreachable server!

Many thanks for your help and quick reply!! 🙂 You made our day! 🙂