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Decommissioned datanode/regionserver: is it safe to remove /dfs directory to free disk-space

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New Contributor

Hi List,


I have disk space limitation on couple of my datanodes (also have regionserver and nodemanager roles on them). It is on a public cloud, I already have the largest disk and they would not give me more disk.
These machines are also running other high-priority processes (other than CDH processes), which needs disk space. So I want to free up space by taking hbase/hdfs off it and distribute the data to other nodes in the cluster.

 

I have decommissioned the nodes and deleted the roles from the hosts but that does not free up /dfs directory on the hosts (still taking most of my disk space).
Is it OK to directly delete the /dfs directory from the nodes, or make it empty? I want the flexibility of adding them back to the cluster at some point of time (may be once I have more disk), if I need to. I am hoping I am not the first one in this situation, any suggestions/work-arounds would be appreciated.

 

Thanks,

Akshay

1 ACCEPTED SOLUTION

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Master Collaborator

Happy to say that our in documentation we have noted that when a DataNode is decommissioned, the data blocks are not removed from the storage directories. You must delete the data manually.

 

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4 REPLIES 4

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New Contributor

Bump up.

Sorry still confused about it.

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Master Collaborator

Happy to say that our in documentation we have noted that when a DataNode is decommissioned, the data blocks are not removed from the storage directories. You must delete the data manually.

 

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New Contributor

Thanks Michalis. 

I believe if I have to add this back to the cluster, those directories (of course based on configurations) would be created again.

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Contributor

Hi, I'm in the same situation. Are there any problems when you add the DataNode back after decomissioning and delete data folder?