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https://issues.apache.org/jira/browse/HADOOP-9160?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13540278#comment-13540278
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Suresh Srinivas commented on HADOOP-9160:
-----------------------------------------

Some thoughts on the proposal:
Some of the admin related functionality such as fsck is on http for a reason. 
The fsck operation takes a long time to complete, could have lot of output 
streamed as response for a long time. That is the reason why http is used. Also 
most of the jmx implementation that is used in deployments today is using 
http+jmx bridge and is used over mostly http. 

I agree some of the points Todd has raised already. The security model is a 
pain in JMX. All the installations that I know of prefer not to use remote jmx, 
instead prefer to use it over http.

I would prefer to use cleaner rest APIs (cleaner than current http JMX bridge) 
than going for JMX.
                
> Adopt JMX for management protocols
> ----------------------------------
>
>                 Key: HADOOP-9160
>                 URL: https://issues.apache.org/jira/browse/HADOOP-9160
>             Project: Hadoop Common
>          Issue Type: Improvement
>            Reporter: Luke Lu
>
> Currently we use Hadoop RPC (and some HTTP, notably fsck) for admin 
> protocols. We should consider adopt JMX for future admin protocols, as it's 
> the industry standard for java server management with wide client support.
> Having an alternative/redundant RPC mechanism is very desirable for admin 
> protocols. I've seen in the past in multiple cases, where NN and/or JT RPC 
> were locked up solid due to various bugs and/or RPC thread pool exhaustion, 
> while HTTP and/or JMX worked just fine.
> Other desirable benefits include admin protocol backward compatibility and 
> introspectability, which is convenient for a centralized management system to 
> manage multiple Hadoop clusters of different versions. Another notable 
> benefit is that it's much easier to implement new admin commands in JMX 
> (especially with MXBean) than Hadoop RPC, especially in trunk (as well as 
> 0.23+ and 2.x).
> Since Hadoop RPC doesn't guarantee backward compatibility (probably not ever 
> for branch-1), there are few external tools depending on it. We can keep the 
> old protocols for as long as needed. New commands should be in JMX. The 
> transition can be gradual and backward-compatible.

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