# EC2 discovery finds some servers, but not all **URL:** \ **Category:** Elasticsearch\ **Created:** [September 11, 2011, 3:28am UTC](https://discuss.elastic.co/t/ec2-discovery-finds-some-servers-but-not-all/5345 "2011-09-11T03:28:14Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Marty1](https://avatars.discourse-cdn.com/v4/letter/m/278dde/32.png) [@Marty1](https://discuss.elastic.co/u/Marty1)\ **Post date:** [September 11, 2011, 3:28am UTC](https://discuss.elastic.co/t/ec2-discovery-finds-some-servers-but-not-all/5345/1 "2011-09-11T03:28:14Z")
I'm having trouble getting any 2 of my EC2 ES boxes to find any other. I turned on more verbosity and see that ES has discovered all 100+ of my servers and listed them. It even tries to connect to port 9300 on a few, but not the right ones. Does ES give up after just a few? ---
**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\ **Post date:** [September 11, 2011, 10:54am UTC](https://discuss.elastic.co/t/ec2-discovery-finds-some-servers-but-not-all/5345/2 "2011-09-11T10:54:21Z")
Are all 100 servers part of the elasticsearch cluster? If not, then I suggest using the ec2 discovery options to reduce (either based on tags or security groups) the servers that will be pinged to include only the elasticsearch servers. There is a parameter called discovery.zen.ping.timeout which defaults to 3s (3 seconds), you can increase it if you want it to be able to ping more servers. On Sun, Sep 11, 2011 at 6:28 AM, Marty [marty@pinterest.com](mailto:marty@pinterest.com) wrote: > I'm having trouble getting any 2 of my EC2 ES boxes to find any > other. I turned on more verbosity and see that ES has discovered all > 100+ of my servers and listed them. It even tries to connect to port > 9300 on a few, but not the right ones. Does ES give up after just a > few? ---
**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, 3:54am UTC](https://discuss.elastic.co/t/ec2-discovery-finds-some-servers-but-not-all/5345/3 "2017-07-06T03:54:49Z")