# Es node suddenly OOM with "fatal error on the network layer"

**URL:** <https://discuss.elastic.co/t/es-node-suddenly-oom-with-fatal-error-on-the-network-layer/177746>\
**Category:** Elasticsearch\
**Created:** [April 21, 2019, 9:31am UTC](https://discuss.elastic.co/t/es-node-suddenly-oom-with-fatal-error-on-the-network-layer/177746 "2019-04-21T09:31:14Z")\
**Posts on this page:** 1\
**Showing post:** 2

<div class="post-metadata">

**Author:** ![DavidTurner](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/davidturner/32/22453_2.png) [@DavidTurner](https://discuss.elastic.co/u/DavidTurner)\
**Post date:** [April 21, 2019, 11:49am UTC](https://discuss.elastic.co/t/es-node-suddenly-oom-with-fatal-error-on-the-network-layer/177746/2 "2019-04-21T11:49:03Z")

</div>

> [@shjdwxy](#):
>
> How to debug this problem ?

By default Elasticsearch will write a heap dump when it encounters an `OutOfMemoryError`. The best thing to do is to open this heap dump (e.g. in [MAT](https://www.eclipse.org/mat/)) and investigate what was using all the heap.

---

_[View the full topic](https://discuss.elastic.co/t/es-node-suddenly-oom-with-fatal-error-on-the-network-layer/177746)._