[ 
https://issues.apache.org/jira/browse/HDFS-15289?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17096266#comment-17096266
 ] 

Uma Maheswara Rao G commented on HDFS-15289:
--------------------------------------------

Thank you [~virajith] and  [~abhishekd] for the reply.
I have created two starting sub JIRAs under this JIRA. 

We can continue to create follow up Jira as we go. I will create one for making 
DFSAdmin to work with ViewFsOverloadScheme.

> Allow viewfs mounts with hdfs scheme and centralized mount table
> ----------------------------------------------------------------
>
>                 Key: HDFS-15289
>                 URL: https://issues.apache.org/jira/browse/HDFS-15289
>             Project: Hadoop HDFS
>          Issue Type: New Feature
>          Components: fs
>    Affects Versions: 3.2.0
>            Reporter: Uma Maheswara Rao G
>            Assignee: Uma Maheswara Rao G
>            Priority: Major
>         Attachments: ViewFSOverloadScheme - V1.0.pdf
>
>
> ViewFS provides flexibility to mount different filesystem types with mount 
> points configuration table. Additionally viewFS provides flexibility to 
> configure any fs (not only HDFS) scheme in mount table mapping. This approach 
> is solving the scalability problems, but users need to reconfigure the 
> filesystem to ViewFS and to its scheme.  This will be problematic in the case 
> of paths persisted in meta stores, ex: Hive. In systems like Hive, it will 
> store uris in meta store. So, changing the file system scheme will create a 
> burden to upgrade/recreate meta stores. In our experience many users are not 
> ready to change that.  
> Router based federation is another implementation to provide coordinated 
> mount points for HDFS federation clusters. Even though this provides 
> flexibility to handle mount points easily, this will not allow 
> other(non-HDFS) file systems to mount. So, this does not solve the purpose 
> when users want to mount external(non-HDFS) filesystems.
> So, the problem here is: Even though many users want to adapt to the scalable 
> fs options available, technical challenges of changing schemes (ex: in meta 
> stores) in deployments are obstructing them. 
> So, we propose to allow hdfs scheme in ViewFS like client side mount system 
> and provision user to create mount links without changing URI paths. 
> I will upload detailed design doc shortly.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org

Reply via email to