# Core connects to local server but immediately drops it (showing red light)

**URL:** <https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210>\
**Category:** Troubleshooting\
**Created:** [September 8, 2015, 2:15am UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210 "2015-09-08T02:15:30Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![helxsz](https://avatars.discourse-cdn.com/v4/letter/h/f0a364/32.png) [@helxsz](https://community.particle.io/u/helxsz)\
**Post date:** [September 8, 2015, 2:15am UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210/1 "2015-09-08T02:15:30Z")

</div>

I have tried the local server, my core can connect the local server which it prints out a line like

```
Connection from: 192.168.43.44, connId: 64
on ready { coreID: '54ff70066667515129371467',
  ip: '192.168.43.44',
  product_id: 0,
  firmware_version: 7,
  cache_key: '_63' }
Core online!

```

once the core seems to be online, the core immediately flashes red light, and tried to restart again, the process takes turn, so core constantly connects to the local server, but then immediately drops it. maybe after several minutes, the core prints out another text saying:

> 1: Core disconnected: socket error Error: read ETIMEDOUT { coreID: '54ff70066667515129371467',  
> cache\_key: '\_38',  
> duration: 617.441 }

how to solve it

---

<div class="post-metadata">

**Author:** ![christine](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/christine/32/5024_2.png) [@christine](https://community.particle.io/u/christine)\
**Post date:** [September 8, 2015, 10:16pm UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210/2 "2015-09-08T22:16:14Z")

</div>

Hey @helxsz. When you say “local server,” do you mean that you have set up the [local cloud](https://github.com/spark/spark-server)?

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<div class="post-metadata">

**Author:** ![helxsz](https://avatars.discourse-cdn.com/v4/letter/h/f0a364/32.png) [@helxsz](https://community.particle.io/u/helxsz)\
**Post date:** [September 9, 2015, 1:03pm UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210/3 "2015-09-09T13:03:28Z")

</div>

yes, I mean the local cloud from the github

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<div class="post-metadata">

**Author:** ![mdma](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/mdma/32/1924_2.png) [@mdma](https://community.particle.io/u/mdma)\
**Post date:** [September 10, 2015, 12:54am UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210/4 "2015-09-10T00:54:50Z")

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Hi @helxsz - what firmware do you have on your Core? You can try flashing tinker to see if that helps:

```auto
particle flash --usb tinker

```

The core should then connect to the local cloud and breathe cyan. Let me know if that resolves the problem, and we can then look at your application to see if there is any issue there.

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<div class="post-metadata">

**Author:** ![helxsz](https://avatars.discourse-cdn.com/v4/letter/h/f0a364/32.png) [@helxsz](https://community.particle.io/u/helxsz)\
**Post date:** [September 10, 2015, 5:05pm UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210/5 "2015-09-10T17:05:07Z")

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Thanks, mdma, this works well now.

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<div class="post-metadata">

**Author:** ![mdma](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/mdma/32/1924_2.png) [@mdma](https://community.particle.io/u/mdma)\
**Post date:** [September 10, 2015, 5:12pm UTC](https://community.particle.io/t/core-connects-to-local-server-but-immediately-drops-it-showing-red-light/15210/6 "2015-09-10T17:12:08Z")

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Great. Then please investigate your application code - the red light indicates some kind of error.

> [@Core Firmware SOS Panic Codes](https://community.particle.io/t/core-firmware-sos-panic-codes/4337):
>
> Are you getting a red flashing LED after running your code on your Spark core? You may be getting a panic code, telling you what went wrong! The panic code is a red LED blinking out SOS (… — …) followed by N flashes, followed by another SOS. Here are the meanings of the N flashes, but #8, out of heap, is the most common: #1 Hard fault #2 Non-maskable interrupt fault #3 Memory Manager fault #4 Bus fault #5 Usage fault #6 Invalid length #7 Exit #8 Out of heap memory #9 SPI over-run #10 Asserti…