question Re: hadoop cluster + what are the configuration steps in order to change the domain name on machines cluster in Support Questions

hadoop cluster + what are the configuration steps in order to change the domain name on machines cluster

mike_bronson7 — Tue, 08 Sep 2020 20:50:59 GMT

We have HDP cluster version `2.6.5` and ambari `2.6.1` version

Cluster include 3 masters machines , and 211 data-nodes machines ( workers machines ) , all machines are `rhel 7.2` version

Example

master1.sys77.com , master2.sys77.com , master3.sys77.com …

And data nodes machines as

worker01.sys77.com , worker02.sys77.com ----> worker211.sys77.com

Now we want to change the domain name to `bigdata.com` instead of `sys77.com`

What is the procedure to replace the `domain name` (`sys77.com`) for Hadoop cluster ? ( HDP cluster with ambari )

Re: hadoop cluster + what are the configuration steps in order to change the domain name on machines cluster

dyadav1 — Wed, 09 Sep 2020 07:18:40 GMT

We can change the Hostname from ambari end as describe in the below article:

https://docs.cloudera.com/HDPDocuments/Ambari-2.5.2.0/bk_ambari-administration/content/ch_changing_host_names.html

Re: hadoop cluster + what are the configuration steps in order to change the domain name on machines cluster

Mike in Austin — Wed, 09 Sep 2020 13:39:22 GMT

If the cluster has TLS/SSL enabled, you'll also need to regenerate certificates.

Also, if Kerberos is enabled, you may need to change the /etc/krb5.conf file if you're changing the kerberos domain and regenerate principals.

Re: hadoop cluster + what are the configuration steps in order to change the domain name on machines cluster

stevenmatison — Thu, 10 Sep 2020 12:43:33 GMT

@mike_bronson7 oddly enough, the top post recommendations is this same question you asked 2 years ago:

https://community.cloudera.com/t5/Support-Questions/how-to-change-hostnames-on-all-machines-in-ambari-cluster/m-p/217984#M179885

To confirm, the hostname and the domain name are one in the same. The "domain.com" is just part of the hostname. The first part is the subdomain. So the procedure to change "domain.com" is the same as subdomain.

HOWEVER, I would highly recommend testing this in a dev cluster before production, especially if you have ssl/kerberos. This is a major change that affects ambari and all components. If the ambari command agains the new json mapping fails, or there is any incomplete action within any agent/component, you are going to bomb the whole cluster.

If this answer resolves your issue or allows you to move forward, please choose to ACCEPT this solution and close this topic. If you have further dialogue on this topic please comment here or feel free to private message me. If you have new questions related to your Use Case please create separate topic and feel free to tag me in your post.

Thanks,

Steven @ DFHZ

Re: hadoop cluster + what are the configuration steps in order to change the domain name on machines cluster

mike_bronson7 — Sun, 13 Sep 2020 16:12:32 GMT

thank you for the post

but another question - according to the document - https://docs.cloudera.com/HDPDocuments/Ambari-2.7.0.0/administering-ambari/content/amb_changing_host_names.html

The last stage is talking about – in case NameNode HA enabled , then need to run the following command on one of the name node

hdfs zkfc -formatZK -force

thank you for the post

but since we have active name node and standby name node we assume that our namenode is HA enable

example from our cluster

but we want to understand what are the risks when doing the following cli on one of the namenode

hdfs zkfc -formatZK -force

is the below command is safety to run without risks ?