Question about master nodes and behaviour

I'm planning to setup ElasticSearch across two datacentres. I know it is
not recommended approach to have the cluster across two data centres, but I
wanted an easy way to replicate the data cross site. I have some doubts
about how many master nodes I should set up.

Scenario 1:
Two master eligible nodes. One in each Site.

discovery.zen.minimum_master_nodes: 2

Site A: Master active

If Site A goes down a new master cannot be elected as min master node is
set to 2.

Question 1: How does site B behave? I believe, no new indexes or documents
can be created but the searches can still be carried out.

Scenario 2:
3 master eligible nodes. Two in Site A and One in Site B.

discovery.zen.minimum_master_nodes: 3/2 +1 = 2

Site A: Master active

If Site A goes down a new master cannot be elected as min master node is
set to 2.

Question 2: What kind master configuration can help mitigate such a
scenario?

Thanks.

--
You received this message because you are subscribed to the Google Groups "elasticsearch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/5525b0c5-600a-4174-a3ab-da17ea63f009%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

This is one reason why we don't recommend such deployments, no matter what
you pick here you risk a split or unavailable cluster.

Thus, there's no good answer and you need to decide what site you are
willing to live without.

On 18 March 2015 at 21:03, Gobin Sougrakpam gobinsougrakpam@gmail.com
wrote:

I'm planning to setup Elasticsearch across two datacentres. I know it is
not recommended approach to have the cluster across two data centres, but I
wanted an easy way to replicate the data cross site. I have some doubts
about how many master nodes I should set up.

Scenario 1:
Two master eligible nodes. One in each Site.

discovery.zen.minimum_master_nodes: 2

Site A: Master active

If Site A goes down a new master cannot be elected as min master node is
set to 2.

Question 1: How does site B behave? I believe, no new indexes or documents
can be created but the searches can still be carried out.

Scenario 2:
3 master eligible nodes. Two in Site A and One in Site B.

discovery.zen.minimum_master_nodes: 3/2 +1 = 2

Site A: Master active

If Site A goes down a new master cannot be elected as min master node is
set to 2.

Question 2: What kind master configuration can help mitigate such a
scenario?

Thanks.

--
You received this message because you are subscribed to the Google Groups
"elasticsearch" group.
To unsubscribe from this group and stop receiving emails from it, send an
email to elasticsearch+unsubscribe@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/elasticsearch/5525b0c5-600a-4174-a3ab-da17ea63f009%40googlegroups.com
https://groups.google.com/d/msgid/elasticsearch/5525b0c5-600a-4174-a3ab-da17ea63f009%40googlegroups.com?utm_medium=email&utm_source=footer
.
For more options, visit https://groups.google.com/d/optout.

--
You received this message because you are subscribed to the Google Groups "elasticsearch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAEYi1X-Cyx7957SqPTgCv7b8RQqD9AV5L32tATRrF19LuqX5QA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.