# Elasticsearch cluster with mixed OS

**URL:** <https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397>\
**Category:** Elasticsearch\
**Created:** [January 5, 2016, 12:00pm UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397 "2016-01-05T12:00:26Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![ori.rubinfeld](https://avatars.discourse-cdn.com/v4/letter/o/7c8e57/32.png) [@ori.rubinfeld](https://discuss.elastic.co/u/ori.rubinfeld)\
**Post date:** [January 5, 2016, 12:00pm UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397/1 "2016-01-05T12:00:26Z")

</div>

Hi,

We would like to perform an OS migration from UBunto to RHEL.  
Our Cluster is 2 nodes, ES Version of 1.3.7 and Logstash 1.4.2

We would like to go to ES 1.7.1 and Logstash 1.5.4  
(\*) ES 1.7.1 because we need the use of http-basic plugin.

I am very limited with resources, And would like to perform the OS migration and ES upgrade on the actual nodes of the cluster.

Can someone consult on the best and safer way to do so ?  
Is it possible to have a two nodes cluster with different OS on each ? (One with UBunto and second with RHEL)

Thanks,

Ori

---

<div class="post-metadata">

**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\
**Post date:** [January 5, 2016, 11:01pm UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397/2 "2016-01-05T23:01:47Z")

</div>

It doesn't really matter too much about the OS. But it _may_ matter with ES.

What's your plan of attack here?

---

<div class="post-metadata">

**Author:** ![ori.rubinfeld](https://avatars.discourse-cdn.com/v4/letter/o/7c8e57/32.png) [@ori.rubinfeld](https://discuss.elastic.co/u/ori.rubinfeld)\
**Post date:** [January 6, 2016, 7:11am UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397/3 "2016-01-06T07:11:15Z")

</div>

Hi,

Cluster with 2 nodes- node1 and node2.  
Each Index has 2 shards with replication factor of 2.

The plan is to take node2 down, then node1 is with primary shards.  
Install RHEL on node2, install ES 1.7.1 and LogStash 1.5.4.  
Join node 2 to the cluster, and the replication process should be able to create the replication shard in node2.  
Cluster should be Green.

Then, take down node1, node2 become the primary.  
Repeat the same Install steps for node1 and connect it to the cluster.

According to DOC's, replication will work from lower release into higher release, but not vice versa, since there might be infrastructure changes for indexes.

Ori

---

<div class="post-metadata">

**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\
**Post date:** [January 6, 2016, 7:12am UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397/4 "2016-01-06T07:12:47Z")

</div>

That will work, but you'd be better off installing the latest 1.7.3, not 1.7.1.

> [@ori.rubinfeld](#):
>
> Each Index has 2 shards with replication factor of 2.

Replication of 2 with a 2 node cluster is pointless, you won't be able to assign the last replica.

---

<div class="post-metadata">

**Author:** ![ori.rubinfeld](https://avatars.discourse-cdn.com/v4/letter/o/7c8e57/32.png) [@ori.rubinfeld](https://discuss.elastic.co/u/ori.rubinfeld)\
**Post date:** [January 6, 2016, 8:07am UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397/5 "2016-01-06T08:07:53Z")

</div>

You are correct, I was mistaking, it is a Replication factor of 1.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 5, 2017, 11:26pm UTC](https://discuss.elastic.co/t/elasticsearch-cluster-with-mixed-os/38397/6 "2017-07-05T23:26:49Z")

</div>


