Thank you all, very helpful information.

1) for server side ELB, what is the PQS health check url path? 

2) Does Phoenix client library support client-side load-balancing? i. e client gets list of PQS addresses from ZK, and performs load balancing. Thus ELB won't be needed. 



On Wed, Aug 7, 2019, 9:01 AM Josh Elser <elserj@apache.org> wrote:
Great answer, Aleksandr!

Also worth mentioning there is only ever one active HBase Master at a
time. If you have multiple started, one will be active as the master and
the rest will be waiting as a standby in case the current active master
dies for some reason (expectedly or unexpectedly).

On 8/7/19 9:55 AM, Aleksandr Saraseka wrote:
> Hello.
> - Phoenix libs should be installed only on RegionServers.
> - QueryServer - it's up to you, PQS can be installed anywhere you want
> - No. QueryServer is using ZK quorum to get everything it needs
> - If you need to balance traffic with multiply PQSs - then yes, but
> again - it's up to you. It is not required multiply PQSs if you have
> multiply HBase masters.
>
> On Wed, Aug 7, 2019 at 12:58 AM jesse <chat2jesse@gmail.com
> <mailto:chat2jesse@gmail.com>> wrote:
>
>     Our cluster used to have one hbase master, now a secondary is added.
>     For phonenix, what changes should we make?
>       - do we have to install new hbase libraries on the new hbase
>     master node?
>     - do we need to install new query server on the hbase master?
>     - any configuration changes should we make?
>     - do we need an ELB for the query server?
>
>     Thanks
>
>
>
>
>
> --
>               Aleksandr Saraseka
> DBA
> 380997600401
> <tel:380997600401> *•* asaraseka@eztexting.com
> <mailto:asaraseka@eztexting.com> *•* eztexting.com
> <http://eztexting.com?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
>
>
> <http://facebook.com/eztexting?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
> <http://linkedin.com/company/eztexting/?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
> <http://twitter.com/eztexting?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
> <https://www.youtube.com/eztexting?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
> <https://www.instagram.com/ez_texting/?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
> <https://www.facebook.com/alex.saraseka?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
> <https://www.linkedin.com/in/alexander-saraseka-32616076/?utm_source=WiseStamp&utm_medium=email&utm_term=&utm_content=&utm_campaign=signature>
>