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Removing host from HDP cluster

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Removing host from HDP cluster

New Contributor

I am trying to delete one host from 2 node hortonworks cluster by using following steps:

1) I stopped all the services from selected host which were running.from Hosts tab > Host Actions > Stop All Components.

2) Stopped ambari agent from selected host.

3) Then click Host Actions > Delete Hosts.

But i am not able to delete the host .It is showing that "

Unable to Delete Host

Deletion of the following 2 components is not supported.
DRPC Server, Storm UI Server"
When i deleted the storm service it worked fine.
So is any there other way for removing host where we need not to delete the services like storm ,metrics collector,grafana etc ?.if we are using service like storm it is mandatory to stop the service?.
please suggest solution for that.
3 REPLIES 3

Re: Removing host from HDP cluster

Hi @sandeep gupta ,

As per Ambari architecture, you can only delete a Host-only if the Host doesnt contain any Master component of any service .

I see your Host was having two components Related to Storm After deleting which the Service will be shown empty.

You should have Stopped the Two components and deleted the components using the Curl command :

curl -u admin:admin -H "X-Requested-By:ambari" -i -X DELETE http://asnaik1.openstacklocal:8080/api/v1/clusters/asnaik/hosts/asnaik3.openstacklocal/host_componen...

And for DRPC Server

curl -u admin:admin -H "X-Requested-By:ambari" -i -X DELETE http://asnaik1.openstacklocal:8080/api/v1/clusters/asnaik/hosts/asnaik3.openstacklocal/host_componen...

where asnaik1.openstacklocal is my ambari server , asnaik is my clustername , asnaik3.openstacklocal is the host which i want to delete , admin:admin is my ambari username and password

and then tried to delete the Host instead of removing the Storm service.

Please let me know if this helps and please login and accept the answer if it did.

Re: Removing host from HDP cluster

New Contributor

Thank you very much akhil .I did the same process and it was working fine.My concern is that ,i need to stop my application which is streaming process if i want to remove any host .This will lead to down time for my application and as we know storm is a streaming process i will lose my data at that point of time.So is there any other way where my storm application will run smoothly and parallelly i can remove host also.

Re: Removing host from HDP cluster

Hi @sandeep gupta,

Unfortunately, There cannot be a case where you can keep the Storm Streaming process running and delete the particular host.

I Hope this delete Host is a one time process and wont be repeated , and it can be done in quick time. You might need to plan production down time if such administrative actions are ongoing.

Please login and accept my answer if you find it helpfull

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