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Install DataNode Role on NameNode/SNN machine

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New Contributor

Hi all,

can I install an HDFS datanode role in machine with installed HDFS NameNode or into machine with SecondaryNameNode?

I use CDH 6.3.2

 

Thanks,

Francesco

2 ACCEPTED SOLUTIONS

avatar
Master Collaborator

@fransyk 

 

Yes, you can have datanode and namenode role together on a host as long as the hardware requirements are met for the service to avoid any out of memory issues.

 

Please refer 

https://docs.cloudera.com/documentation/enterprise/6/release-notes/topics/rg_hardware_requirements.h...

 

Hope this helps,
Paras
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View solution in original post

avatar
Master Collaborator

@fransyk 

 

It is not compulsory to have both the roles on different hosts. 

Having said that, in production environments it is recommended to differentiate worker hosts and master hosts.

 

Please refer below document for recommended role allocations for different cluster sizes:

 

https://docs.cloudera.com/documentation/enterprise/latest/topics/cm_ig_host_allocations.html#concept...

 

Hope this helps,
Paras
Was your question answered? Make sure to mark the answer as the accepted solution.
If you find a reply useful, say thanks by clicking on the thumbs up button.

 

View solution in original post

4 REPLIES 4

avatar
Master Collaborator

@fransyk 

 

Yes, you can have datanode and namenode role together on a host as long as the hardware requirements are met for the service to avoid any out of memory issues.

 

Please refer 

https://docs.cloudera.com/documentation/enterprise/6/release-notes/topics/rg_hardware_requirements.h...

 

Hope this helps,
Paras
Was your question answered? Make sure to mark the answer as the accepted solution.
If you find a reply useful, say thanks by clicking on the thumbs up button.

avatar
New Contributor

avatar
Master Collaborator

@fransyk 

 

It is not compulsory to have both the roles on different hosts. 

Having said that, in production environments it is recommended to differentiate worker hosts and master hosts.

 

Please refer below document for recommended role allocations for different cluster sizes:

 

https://docs.cloudera.com/documentation/enterprise/latest/topics/cm_ig_host_allocations.html#concept...

 

Hope this helps,
Paras
Was your question answered? Make sure to mark the answer as the accepted solution.
If you find a reply useful, say thanks by clicking on the thumbs up button.

 

avatar
Contributor

The data node question has been answered, but one tangental comment - you say you are using the Secondary Name Node service. You almost certainly do not want to be using that. You do not get any HA with the SNN. What you probably want is the Standby Namenode. In Cloudera Manager you can enable HA from the HDFS service actions and that will replace your Secondary Name Node with a Standby Name Node.