Questions-56: In some situations, you may have to change the host name. So what are the implications of this?

Answer: This is not a simple change, of you want to do that then you must update the Ambari and all the hosts of new names.

Question-57: What all steps you have to do, if you need to change the Ambari hosts itself?

Answer: In this case on the new host we need to install the Ambari server first and then transfer the data from existing Ambari database to the new Ambari Database.

Question-58: What is the default username and password for the PostGresSQL database used by Ambari?

Answer: It has username as ambari and password as bigdata.

Question-59: What all are the feature of LZO compression compare to any other compression technology?

Answer: This has unique feature of lossless data compression and also more focuses on the speed rather than compression ratio.

Question-60: Is by default LZO installed on the HDP cluster or on Ambari server?

Answer: By default, Ambari does not install or enable the LZO compression libraries. As an administrator you have to explicitly do that. So if want to enable the LZO compression in our HDP cluster then we must have to install LZO compression libraries throughout the cluster. And should configure the same in core-site.xml file.