# How do I confirm DNS round robin is working correctly? **URL:** \ **Category:** Logstash\ **Created:** [April 12, 2017, 1:49am UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068 "2017-04-12T01:49:59Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![red888](https://avatars.discourse-cdn.com/v4/letter/r/ecae2f/32.png) [@red888](https://discuss.elastic.co/u/red888)\ **Post date:** [April 12, 2017, 1:49am UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/1 "2017-04-12T01:49:59Z")
I have logstash pointing to a round robin DNS record: ``` elasticsearch { hosts => my.cluster.com index => "myindex" ....etc ``` How can I confirm logstash is load balancing across all those servers? Or more importantly if its only going to one of those servers? ---
**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:** [April 12, 2017, 3:37am UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/2 "2017-04-12T03:37:32Z")
I don't think LS will load balance based on multiple DNS entries will it? The docs aren't really clear on that. ---
**Author:** ![red888](https://avatars.discourse-cdn.com/v4/letter/r/ecae2f/32.png) [@red888](https://discuss.elastic.co/u/red888)\ **Post date:** [April 12, 2017, 1:45pm UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/3 "2017-04-12T13:45:01Z")
I thought it did. According to the docs elasticsearch and logstash support round robin. If logstash only uses round robin for failover then I guess I cant use it. Right now I have logstash outputting to three nodes in my cluster ---
**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\ **Post date:** [April 12, 2017, 2:00pm UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/4 "2017-04-12T14:00:46Z")
If you just specify one URL, I suspect it will look like a single node to Logstash. Logstash will generally use multiple connections, which with your setup is likely to hit multiple nodes, but I do not see any way for Logstash to control the distribution. ---
**Author:** ![red888](https://avatars.discourse-cdn.com/v4/letter/r/ecae2f/32.png) [@red888](https://discuss.elastic.co/u/red888)\ **Post date:** [April 12, 2017, 2:19pm UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/5 "2017-04-12T14:19:25Z")
Hang on just want to confirm this: Right now I have the logstash "hosts" parameter set to 3 different IP addresses. Are you saying that logstash isn't load balancing across these addresses? Maybe I always misunderstood how this works. ---
**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\ **Post date:** [April 12, 2017, 2:28pm UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/6 "2017-04-12T14:28:57Z")
If you specify 3 node IPs, Logstash knows about them and can handle load distribution. ---
**Author:** ![red888](https://avatars.discourse-cdn.com/v4/letter/r/ecae2f/32.png) [@red888](https://discuss.elastic.co/u/red888)\ **Post date:** [April 12, 2017, 2:34pm UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/7 "2017-04-12T14:34:13Z")
OK good so at least that is doing what I think it is. But we aren't sure that if I specify a single DNS entry with multiple A records for the hosts parameter logstash is smart enough to load balance across all IPs it receives from my round robin enabled DNS server for that record- right? ---
**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:** [April 13, 2017, 3:38am UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/8 "2017-04-13T03:38:52Z")
> [@red888](#): > > But we aren't sure that if I specify a single DNS entry with multiple A records for the hosts parameter logstash is smart enough to load balance across all IPs it receives from my round robin enabled DNS server for that record- right? Yes, that is what I was referring to. Not multiple host entries in the config file. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [May 11, 2017, 3:52am UTC](https://discuss.elastic.co/t/how-do-i-confirm-dns-round-robin-is-working-correctly/82068/9 "2017-05-11T03:52:09Z")
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