# Visualizer Docker - Issue running EGL Demo on EC2
**URL:** https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615
**Category:** Web Support
**Created:** [October 21, 2020, 6:52pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615 "2020-10-21T18:52:00Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@SanderDiabatix](https://discourse.paraview.org/u/SanderDiabatix)
#### Post date: [October 21, 2020, 6:52pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/1 "2020-10-21T18:52:00Z")
Hey,
I am following the tutorial at [https://kitware.github.io/paraviewweb/docs/docker.html](https://kitware.github.io/paraviewweb/docs/docker.html) step-by-step, managing to browse to the demo page. But when selecting the Visualizer application, I am greeted with “Server disconnected” underneath the spinning logo after a couple of seconds.
Checking the console show:
```
WebSocket connection to 'ws://localhost/proxy?sessionId=e5e621fe-13cc-11eb-a18e-0242ac110002&path=ws' failed: Error in connection establishment: net::ERR_CONNECTION_REFUSED
```
Since the paraview application is running on an EC2 instance, I would suspect this address should point to the EC2 server (eg. [ec2-myinstancename.eu-central-1.compute.amazonaws.com](http://ec2-myinstancename.eu-central-1.compute.amazonaws.com)) instead of localhost.
Visiting localhost:9000/visualizer locally on the EC2 machine results in no issues.
What could I have misconfigured?
Kind Regards,
Sander
---
### Author:  [@jourdain](https://discourse.paraview.org/u/jourdain)
#### Post date: [October 21, 2020, 7:17pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/2 "2020-10-21T19:17:05Z")
When you run your docker, you need to provide the correct server name.
`-e "SERVER_NAME=pvw.company.com" `
---
### Author:  [@SanderDiabatix](https://discourse.paraview.org/u/SanderDiabatix)
#### Post date: [October 21, 2020, 7:26pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/3 "2020-10-21T19:26:21Z")
Hi Sebastien,
I have provided this and double checked by running _printenv_ inside the container.
It shows:
```
SERVER_NAME=ec2-myinstancename.eu-central-1.compute.amazonaws.com
```
Is there something else I should check?
---
### Author:  [@jourdain](https://discourse.paraview.org/u/jourdain)
#### Post date: [October 21, 2020, 8:02pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/4 "2020-10-21T20:02:35Z")
This should do the trick. I’m not sure what is happening.
Which image are you using? The latest to date can be found [here](https://hub.docker.com/r/kitware/paraview/tags) and should start with `pvw-*`.
@Scott_Wittenburg could you point to the documentation showing the usage of those `paraview/pvw-*` image. Normally they should behave the same way as they are currently described in the pvw docs that you are following.
---
### Author:  [@SanderDiabatix](https://discourse.paraview.org/u/SanderDiabatix)
#### Post date: [October 21, 2020, 8:09pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/5 "2020-10-21T20:09:31Z")
This is the full command:
```
sudo docker run --gpus all -p 0.0.0.0:9000:80 -v ~/data:/data -e "SERVER_NAME=ec2-myinstancename.eu-central-1.compute.amazonaws.com" -e "PROTOCOL=ws" --restart unless-stopped -dti kitware/paraviewweb:pvw-egl-demo-v5.6.0
```
So that would be: _pvw-egl-demo-v5.6.0_
I just noticed I am running on Ubuntu 20.04 though, while the guide asumes 16 or 18. Could this cause the issue? I can try with 16.04 tomorrow.
---
### Author:  [@Scott\_Wittenburg](https://discourse.paraview.org/u/Scott_Wittenburg)
#### Post date: [October 21, 2020, 8:24pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/6 "2020-10-21T20:24:15Z")
Here [1] is some documentation specific to the `paraview-pvw-*` images Sebastien mentioned, but I agree the parts related to how the session url is configured should be the same.
The images with “demo” in the name are kind of outdated. I think Sebastien is referring to the images with just the paraview version and rendering type in their name. For example the latest egl image for python3 is:
kitware/paraview:pvw-v5.8.0-egl-py3
The documentation in [1] is for those images (no “demo” or “visualizer” in the image name), where you expect to host your web application in a directory on your machine, and the docker container just mounts that directory and runs it. The general idea of that approach is described here [2], under “fully external direct run”.
[1] [https://kitware.github.io/paraviewweb/docs/docker\_cheatsheet.html](https://kitware.github.io/paraviewweb/docs/docker_cheatsheet.html)
[2] [https://kitware.github.io/paraviewweb/docs/container\_overview.html#Layer-Two-ParaViewWeb](https://kitware.github.io/paraviewweb/docs/container_overview.html#Layer-Two-ParaViewWeb)
Hope it helps,
Scott
---
### Author:  [@SanderDiabatix](https://discourse.paraview.org/u/SanderDiabatix)
#### Post date: [October 22, 2020, 12:01pm UTC](https://discourse.paraview.org/t/visualizer-docker-issue-running-egl-demo-on-ec2/5615/7 "2020-10-22T12:01:54Z")
Hi Scott, Sebastien
I was able to set up an instance using the kitware/paraview:pvw-v5.7.1-egl-py3 image.
I encountered another issue on the 5.8.0 version where the connection would timeout, but that was probably due to a misconfiguration on my side.
Thank you for the assistance,
Sander