Hi Vivek,

We are running multiple instances of Livy on our clusters. Our users can
create and access jobs on any of the Livy instances.

To answer your particular question

*1. Is this feature available in the 0.3 release?* No. The feature is not
available out of the box–we modified Livy to add this feature.
*2. How would I name/number the multiple instances I bring up?* The load
balancer knows all the instances. Users only interact with the load
balancer.
*3. How does one load balance and send requests across the multiple
instances?* Livy instances do not know that requests come from a load
balancer. Each processes requests it receives and updates a shared *"session
store"*, which we implemented on top of ZooKeeper.
*4. Does Livy have a heartbeat mechanism to understand which or how many
instances are up?* No. There is a heartbeat mechanism in Livy, but we do
not using it to detect live/dead Livy instances. Each instance only reacts
to the updates to the ZooKeeper *"session store"*, which is shared by all
instances of Livy.

Thanks,
Meisam

On Wed, Jul 26, 2017 at 1:36 AM Vivek <[email protected]> wrote:

> Ok.so if I start multiple instances how will I know which instance to send
> the request to?
> And multiple instances would then be only controlled by the port id?
>
>
> Sent from my iPhone
>
> On 26 Jul 2017, at 4:04 PM, Saisai Shao <[email protected]> wrote:
>
> Current Livy doesn't support the things you mentioned here. You can start
> multiple Livy in the cluster, but each LivyServer is a standalone service
> doesn't aware the existence of others.
>
> On Wed, Jul 26, 2017 at 10:27 AM, Vivek <[email protected]> wrote:
>
>> Hi,
>>
>> We are now considering moving into a uat environment using Livy at my
>> company.
>>
>> Has anyone implemented multiple Livy instances on a single cluster with
>> load balancing?
>>
>> A few questions.
>> 1. Is this feature available in the 0.3 release?
>> 2. How would I name/number the multiple instances I bring up?
>> 3. How does one load balance and send requests across the multiple
>> instances?
>> 4. Does Livy have a heartbeat mechanism to understand which or how many
>> instances are up?
>>
>> Any answers would be appreciated.
>>
>> Regards
>> Vivek
>>
>>
>> Sent from my iPhone
>>
>
>

Reply via email to