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Zookeeper, mail # user - Zookeeper Setup

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RE: Zookeeper Setup
Rakesh R 2013-11-22, 09:44

I hope this provides a bit of information, when running a ZooKeeper ensemble.
I'll try to cover few important configurations/parameters which will be helpful to manage the cluster:

1) Create file myid at three places and should have unique value like 1,2,3

2) Verify all the three machines has same value of server information. For example, shown below:

3) Update /etc/hosts file on each machine to add the host names being used in the zookeeper configuration

4) initLimit : Timeouts ZooKeeper uses to limit the length of time the. ZooKeeper servers in quorum have to connect to a leader.

5) syncLimit : Limits how far out of date server can be from a leader.

6) tickTime  : The fundamental unit of time in ZooKeeper measured in milliseconds. It is used to regulate timeouts. With both of these timeouts, you specify the unit of time using tickTime in miliseconds.

7) Java heap size : Please give attention to the java max heap size

8) Monitor network & disk I/O : There will be frequent data transferring between the quorum peers for leader election, write operations etc.
The main reason you want to do this is to avoid any contention with other processes for both network and disk I/O. If you run other I/O and/or CPU-intensive processes on the same machines you are running a ZooKeeper node, you will likely see connection timeouts and other issues due to contention. I've seen this happen in production systems, and as soon as the ZooKeeper nodes were moved to their own dedicated machines, the connection loss problems disappeared

9) ZNode size limit:  1MB is the default size of a single zNode or key/value pair within ZooKeeper. ZooKeeper is designed as a high read, high throughput system for small keys. It is not designed as a large data store to hold very large data values. As such this 1MB value is a default config option and can be overridden. It is not advised to do so - but increasing the size a little bit will probably not damage your system (it all depends on your unique access patterns and these changes should be made with care and at your own risk).
I recommend reading following for more information:
 - http://zookeeper.apache.org/doc/r3.3.2/zookeeperAdmin.html#sc_designing
 - ZooKeeper wiki for more details : https://cwiki.apache.org/confluence/display/ZOOKEEPER/Index
-----Original Message-----
From: Techy Teck [mailto:[EMAIL PROTECTED]]
Sent: 22 November 2013 13:16
To: user
Subject: Re: Zookeeper Setup

On Thu, Nov 21, 2013 at 9:38 AM, Techy Teck <[EMAIL PROTECTED]> wrote:

> I recently have got three Ubuntu VM's in which I am supposed to setup
> Zookeeper.
> This is the first time I will be setting up Zookeeper, is there any
> best practice that I am supposed to use while setting up the Zookeeper
> across all those three VM's?
> Any documentation or step by step guidance will be helpful..