​What does "Recovery Host" do in Ambari 2.6.2.2?

[#1]

What does "Recovery Host" do in Ambari 2.6.2.2?

I found "Recovery Host" in "Host Actions". I learned that this functionality is enabled if all the components on the host are stopped. And then, after stopping all the components and click "Recovery Host", the confirmation window appeared and it shows "This action will completely re-install all components on this host." What does "completely re-install" mean? Additionally, as far as I tried, nothing happened when I clicked "Yes" on the confirmation window.

[#2 · Accepted solution]

@Takefumi Oide

Recover Host feature was added in the UI as part of JIRA: https://issues.apache.org/jira/browse/AMBARI-21929.
UI task for Host Recovery

https://github.com/apache/ambari/commit/bb4645f7c0e8242a397b192cabd326bef0d99700

As per the fix:
This action will completely re-install all components on this host, and should only be used when restoring a host using replacement hardware. Host cannot be recovered unless every host component is not in Stopped, Install Failed or Init state

[#3]

Hi @jsensharma ,

Is there any rest API call available for this recovery host option.

That will be very helpful.

Thanks,

Bhuban

[#4]

Thanks, @Jay Kumar SenSharma

These days your comments help me a lot! Thank you very much!

[#5]

Hi Jay Kumar SenSharma ,

Can you please address my issue with the host recovery from Ambari after OS upgraded from RHEL 6 to RHEL 7.

https://community.hortonworks.com/questions/242900/recover-host-on-ambari-26-creating-only-kerberos-...