# Communication between non-primary containers becomes unavailable

**URL:** <https://discuss.circleci.com/t/communication-between-non-primary-containers-becomes-unavailable/24173>\
**Category:** Bug Reports\
**Tags:** docker, 2.0\
**Created:** [August 9, 2018, 8:19am UTC](https://discuss.circleci.com/t/communication-between-non-primary-containers-becomes-unavailable/24173 "2018-08-09T08:19:27Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![tagomoris](https://sea2.discourse-cdn.com/circleci/user_avatar/discuss.circleci.com/tagomoris/32/13087_2.png) [@tagomoris](https://discuss.circleci.com/u/tagomoris)\
**Post date:** [August 9, 2018, 8:19am UTC](https://discuss.circleci.com/t/communication-between-non-primary-containers-becomes-unavailable/24173/1 "2018-08-09T08:19:27Z")

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We’re using 3 containers, which are [a] primary container (Ubuntu), [b] MySQL and [c] private container of related private app, and [c] is used to initialize MySQL database schema/data by running `rake db:migrate` or similar commands. Of course, it requires connection between [c] and [b]. After initialization, tests are executed on primary container.

Two week ago (when we started to use this configuration), this configuration works well.  
But 9 hours ago, the connection between [b] and [c] seems to become unavailable.

Is this a kind of bug? Or results of intentional CircleCI update?

This is strongly required for us to use different container images from testing repository to test on schema/data defined by different repository.  
It is impossible as documented to use remote docker environment, so that the current configuration is only a hack to do it for us.

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<div class="post-metadata">

**Author:** ![halfer](https://sea2.discourse-cdn.com/circleci/user_avatar/discuss.circleci.com/halfer/32/9083_2.png) [@halfer](https://discuss.circleci.com/u/halfer)\
**Post date:** [August 9, 2018, 9:37am UTC](https://discuss.circleci.com/t/communication-between-non-primary-containers-becomes-unavailable/24173/2 "2018-08-09T09:37:09Z")

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> [@tagomoris](#):
>
> But 9 hours ago, the connection between [b] and [c] seems to become unavailable.

It should be fine, I think. CircleCI merges the networking stacks of all primary and secondary containers to localhost for ease of use. I would start off by checking you’re using the right address/port in [c] when connecting to [b].

However, I imagine most people’s use-case is to call secondary containers only from the primary [a], so it is possible you’ve bumped into a bug.

> [@tagomoris](#):
>
> It is impossible as documented to use remote docker environment, so that the current configuration is only a hack to do it for us.

Can you expand on why that is impossible? I use a single primary container, pull ~12 images from a private registry, and then start them on Docker Compose. It works flawlessly. Could you do the same?