# Popen with ping doesn't work in a Docker container **URL:** \ **Category:** Ignition\ **Created:** [June 2, 2021, 3:56pm UTC](https://forum.inductiveautomation.com/t/popen-with-ping-doesnt-work-in-a-docker-container/47355 "2021-06-02T15:56:38Z")\ **Posts on this page:** 1\ **Showing post:** 16
**Author:** ![Kevin.Collins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.collins/32/13497_2.png) [@Kevin.Collins](https://forum.inductiveautomation.com/u/Kevin.Collins)\ **Post date:** [June 20, 2021, 10:50pm UTC](https://forum.inductiveautomation.com/t/popen-with-ping-doesnt-work-in-a-docker-container/47355/16 "2021-06-20T22:50:23Z")
> [@ken.maze](#): > > `At least one invalid signature was encountered.` Based on some additional research ([this thread](https://askubuntu.com/questions/1263284/apt-update-throws-signature-error-in-ubuntu-20-04-container-on-arm) included), I think you're facing the issue with `libseccomp2` on your host Pi system. Take a look at this forum thread for more insights: [Docker Container Does Not Start - #4 by kcollins](http://forum.inductiveautomation.com/t/docker-container-does-not-start/43915/4) First thing I'd do is a `sudo apt-get update && sudo apt-get upgrade` on your Pi and try the build again. If this works, we should probably add that guidance to the other thread (since users would no longer need to go manually update that library and instead be able to have the system take care of the update). I'm running Ubuntu 21.04 64-bit on my Pi system (discussed briefly [here](http://forum.inductiveautomation.com/t/maker-install-on-raspberry-pi/47496/6)) which is already running libseccomp2 v2.5.1... I can't say whether that is necessarily a good option if you're making use of RaspPi GPIO, I haven't done any hardware projects under Ubuntu on RaspPi yet... --- _[View the full topic](https://forum.inductiveautomation.com/t/popen-with-ping-doesnt-work-in-a-docker-container/47355)._