# Elasticsearch AWS availability zone awareness **URL:** \ **Category:** Elasticsearch\ **Created:** [October 10, 2013, 8:37am UTC](https://discuss.elastic.co/t/elasticsearch-aws-availability-zone-awareness/13902 "2013-10-10T08:37:51Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![nicktgr15](https://avatars.discourse-cdn.com/v4/letter/n/65b543/32.png) [@nicktgr15](https://discuss.elastic.co/u/nicktgr15)\ **Post date:** [October 10, 2013, 8:37am UTC](https://discuss.elastic.co/t/elasticsearch-aws-availability-zone-awareness/13902/1 "2013-10-10T08:37:51Z")
Hello, I have a question regarding elasticsearch AWS availability zone awareness which I will attempt to describe with an example. Let's suppose that we have an elasticsearch cluster running on eu-west-1 with 2 nodes (ec2 instances) per zone (3 availability zones, 6 nodes in total). To my understanding, in the event of a zone failure if shards were replicated between nodes of the same zone the cluster will not be able to completely recover. Is this the case or elasticsearch is aware of the AWS zones in a region and tries to replicate shards to nodes in different zones? Regards, Nick -- 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](mailto:elasticsearch+unsubscribe@googlegroups.com). For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). ---
**Author:** ![javanna](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/javanna/32/4698_2.png) [@javanna](https://discuss.elastic.co/u/javanna)\ **Post date:** [October 10, 2013, 12:22pm UTC](https://discuss.elastic.co/t/elasticsearch-aws-availability-zone-awareness/13902/2 "2013-10-10T12:22:24Z")
Correct. You need to configure awareness in order to make each area as independent as possible, so that you possibly have a whole copy of the data in each zone. Have a look at the reference to know how to do it: [Elasticsearch Platform — Find real-time answers at scale | Elastic](http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/modules-cluster.html) . Cheers Luca On Thursday, October 10, 2013 10:37:51 AM UTC+2, nicktgr15 wrote: > Hello, > > I have a question regarding elasticsearch AWS availability zone awareness > which I will attempt to describe with an example. > Let's suppose that we have an elasticsearch cluster running on eu-west-1 > with 2 nodes (ec2 instances) per zone (3 availability zones, 6 nodes in > total). > To my understanding, in the event of a zone failure if shards were > replicated between nodes of the same zone the cluster will not be > able to completely recover. > Is this the case or elasticsearch is aware of the AWS zones in a region > and tries to replicate shards to nodes in different zones? > > Regards, > Nick -- 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](mailto:elasticsearch+unsubscribe@googlegroups.com). For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). ---
**Author:** ![nicktgr15](https://avatars.discourse-cdn.com/v4/letter/n/65b543/32.png) [@nicktgr15](https://discuss.elastic.co/u/nicktgr15)\ **Post date:** [October 11, 2013, 4:00pm UTC](https://discuss.elastic.co/t/elasticsearch-aws-availability-zone-awareness/13902/3 "2013-10-11T16:00:24Z")
Thanks for the quick reply Luca. It looks like what I was looking for. Regards, Nick On Thursday, October 10, 2013 1:22:24 PM UTC+1, Luca Cavanna wrote: > Correct. You need to configure awareness in order to make each area as > independent as possible, so that you possibly have a whole copy of the data > in each zone. > > Have a look at the reference to know how to do it: > [Elasticsearch Platform — Find real-time answers at scale | Elastic](http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/modules-cluster.html). > > Cheers > Luca > > On Thursday, October 10, 2013 10:37:51 AM UTC+2, nicktgr15 wrote: > > > Hello, > > > > I have a question regarding elasticsearch AWS availability zone awareness > > which I will attempt to describe with an example. > > Let's suppose that we have an elasticsearch cluster running on eu-west-1 > > with 2 nodes (ec2 instances) per zone (3 availability zones, 6 nodes in > > total). > > To my understanding, in the event of a zone failure if shards were > > replicated between nodes of the same zone the cluster will not be > > able to completely recover. > > Is this the case or elasticsearch is aware of the AWS zones in a region > > and tries to replicate shards to nodes in different zones? > > > > Regards, > > Nick -- 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](mailto:elasticsearch+unsubscribe@googlegroups.com). For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). ---
**Author:** ![Pierce\_Wetter](https://avatars.discourse-cdn.com/v4/letter/p/65b543/32.png) [@Pierce\_Wetter](https://discuss.elastic.co/u/Pierce_Wetter)\ **Post date:** [October 11, 2013, 6:16pm UTC](https://discuss.elastic.co/t/elasticsearch-aws-availability-zone-awareness/13902/4 "2013-10-11T18:16:07Z")
We do this as follows: Somewhere: zone=`/usr/bin/curl -s /dev/null http://169.254.169.254/latest/meta-data/placement/availability-zone` export AWS\_ZONE=$zone config/elasticsearch.yml: node.awszone: ${AWS\_ZONE} cluster.routing.allocation.awareness.attributes: awszone Gotchas: You have to set the minimum master nodes to be 1 greater than the maximum number of nodes you have in a zone. That prevents elastic search from nominating a new primary unless it can see two zones. That's because it turns out that zones lose communication with each other on a regular basis. Not for long, but long enough for Elasticsearch to detect it and split brain especially if you have it set to the default of 1. We have 4 zones, 6 nodes. 2 West zones of 2 nodes each, 2 East zones of 1 node each. East would lose contact with West and split brain. You need 0.90.5 at least, because there's a bug fix in there relating to allocating shards that wouldn't balance if you didn't have an equal number of nodes in each zone. There may be an additional problem relating to primary allocation, as I now have all the primary shards on one node. -- 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](mailto:elasticsearch+unsubscribe@googlegroups.com). For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 2:12am UTC](https://discuss.elastic.co/t/elasticsearch-aws-availability-zone-awareness/13902/5 "2017-07-06T02:12:49Z")