# How to read erl\_crash.dump

**URL:** <https://community.fly.io/t/how-to-read-erl-crash-dump/20404>\
**Category:** Questions / Help\
**Tags:** elixir, login-only\
**Created:** [June 18, 2024, 8:56am UTC](https://community.fly.io/t/how-to-read-erl-crash-dump/20404 "2024-06-18T08:56:45Z")\
**Posts on this page:** 1\
**Showing post:** 2

<div class="post-metadata">

**Author:** ![lubien](https://sea1.discourse-cdn.com/fly1/user_avatar/community.fly.io/lubien/32/41919_2.png) [@lubien](https://community.fly.io/u/lubien)\
**Post date:** [June 18, 2024, 11:49am UTC](https://community.fly.io/t/how-to-read-erl-crash-dump/20404/2 "2024-06-18T11:49:50Z")

</div>

I’ve had to debug a bug previously when the machine [exited with no elixir logs](https://community.fly.io/t/fixed-mysql-support-for-phoenix-and-ecto/19983). I’ve changed my Dockerfile to:

```auto
- CMD ["/app/bin/server"]
+ CMD ["sleep", "infinity"]

```

Then you can deploy once more and fly ssh console. Do note your app will not be online during that time.

This post has more debugging tips:

> [@Fixed MySQL support for Phoenix and Ecto](https://community.fly.io/t/fixed-mysql-support-for-phoenix-and-ecto/19983):
>
> A few weeks ago one of our customers, @iagoangelimc , noticed that something felt off connecting their Phoenix app to their deployed MySQL instance. We brainstormed a lot about what could have happened and with help of @jstiebs we found out this was actually a MyXQL issue, that’s the library that Ecto uses behind the scenes. Passing settings such as socket\_options: [:inet6] to enable IPv6 from Phoenix to MySQL wasn’t being properly set then @iagoangelimc quickly sent a fix to the repo and it’s…

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_[View the full topic](https://community.fly.io/t/how-to-read-erl-crash-dump/20404)._