Zookeeper leader election

[#1]

if I have 5 zookeeper nodes and from that 5 zookeeper nodes one 1 zookeeper nodes goes down which was leader node then how zookeeper will elect the new leader from the remaining 4 zookeeper node?

[#2 · Accepted solution]

@Big-dAta ,

A quorum in a ZooKeeper ensemble is a group of servers with more than half of the total number of servers in the ensemble. So for an ensemble of 5 servers, the quorum is 3 servers.

As long as there are 3 servers available an election can always be carried out.

So, in your example, the 4 remaining servers will talk to each other and decide who will be the new leader.

Cheers,

André

[#3 · Accepted solution]

@Big-dAta ,

A quorum in a ZooKeeper ensemble is a group of servers with more than half of the total number of servers in the ensemble. So for an ensemble of 5 servers, the quorum is 3 servers.

As long as there are 3 servers available an election can always be carried out.

So, in your example, the 4 remaining servers will talk to each other and decide who will be the new leader.

Cheers,

André

[#4]

Thank you mate, & what if 3 of my zookeeper are down? What I can do at that time 

[#5 · Accepted solution]

Then the service will be unavailable until you recover at least one of them.