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https://issues.apache.org/jira/browse/PHOENIX-3654?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15864715#comment-15864715
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Josh Elser commented on PHOENIX-3654:
-------------------------------------

bq. You can set a read-only ACL that doesn't need auth.

Yup, AFAIK, that's not a big deal.

bq. You can build a service discovery mechanism backed by ZooKeeper yet 
providing its own client facing API that is not kerberized. ANd so on.

Yes! This is ultimately what I'd like to see some more thought put into. There 
are _tons_ of options that could be leveraged. Would be nice to see some simple 
pros/cons laid out so we can back up why one was chosen over others :)

> Load Balancer for thin client
> -----------------------------
>
>                 Key: PHOENIX-3654
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-3654
>             Project: Phoenix
>          Issue Type: New Feature
>    Affects Versions: 4.8.0
>         Environment: Linux 3.13.0-107-generic kernel, v4.9.0-HBase-0.98
>            Reporter: Rahul Shrivastava
>             Fix For: 4.9.0
>
>   Original Estimate: 240h
>  Remaining Estimate: 240h
>
> We have been having internal discussion on load balancer for thin client for 
> PQS. The general consensus we have is to have an embedded load balancer with 
> the thin client instead of using external load balancer such as haproxy. The 
> idea is to not to have another layer between client and PQS. This reduces 
> operational cost for system, which currently leads to delay in executing 
> projects.
> But this also comes with challenge of having an embedded load balancer which 
> can maintain sticky sessions, do fair load balancing knowing the load 
> downstream of PQS server. In addition, load balancer needs to know location 
> of multiple PQS server. Now, the thin client needs to keep track of PQS 
> servers via zookeeper ( or other means). 
> In the new design, the client ( PQS client) , it is proposed to  have an 
> embedded load balancer.
> Where will the load Balancer sit ?
> The load load balancer will embedded within the app server client.  
> How will the load balancer work ? 
> Load balancer will contact zookeeper to get location of PQS. In this case, 
> PQS needs to register to ZK itself once it comes online. Zookeeper location 
> is in hbase-site.xml. It will maintain a small cache of connection to the 
> PQS. When a request comes in, it will check for an open connection from the 
> cache. 
> How will load balancer know load on PQS ?
> To start with, it will pick a random open connection to PQS. This means that 
> load balancer does not know PQS load. Later , we can augment the code so that 
> thin client can receive load info from PQS and make intelligent decisions.  
> How will load balancer maintain sticky sessions ?
> While we still need to investigate how to implement sticky sessions. We can 
> look for some open source implementation for the same.
> How will PQS register itself to service locator ?
> PQS will have location of zookeeper in hbase-site.xml and it would register 
> itself to the zookeeper. Thin client will find out PQS location using 
> zookeeper.



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