How to import a config file into Docker Container of Logstash?

Elastic Stack Logstash
1

Hi Logstash Ninja Masters,

I recently spun up a Logstash docker container (v 7.4.0), to replace a local-app version of LS on the same Ubuntu box. I‘m confused how to instruct the Docker LS to use the configuration that the local-app LS used?

Some details:

My host machine is Ubuntu 16.04.4, and my Docker version is 17.09.0-ce. For the moment, I want a simple standalone LS docker instance. By that, I mean I don’t want to worry about pipeline files, I don’t want to use docker-compose. Here’s my docker run command:

docker run --rm -it -d \
    -v /usr/share/logstash/config/logstash.conf:/home/me/logstash/logstash-7.4.0/config/myConfig.conf
    --name myLogstash \
    --net myNet \
    -e XPACK.MONITORING_ELASTICSEARCH_HOSTS="http://10.10.10.100:9200" \
    docker.elastic.co/logstash/logstash:7.4.0

That second line is my clumsy attempt to tell Docker LS, “Hey, be sure to import and use this local config file, okay?”

The container comes up great:

me@ubuntu1:~# docker ps
CONTAINER ID        IMAGE                 COMMAND                  CREATED             STATUS              PORTS                                                                              NAMES
8ec488b628f5        c2c1ac6b995b          "/usr/local/bin/do..."   2 hours ago         Up 2 hours          5044/tcp, 9600/tcp                                                                 myLogstash
me@ubuntu1:~#

So… the container comes up, but I don’t think its using my config file.

How do I force the Docker LS to do that? I’ve tried copying the desired file into the container’s /usr/share/logstash/config/ directory; no effect. Can I do that and somehow restart the service?

Some other questions I have that aren’t address in the documentation… From running the local version of LS, I learned that you launched the LS service like this:

~bin/logstash -r -f config/myConfig.conf

Basically, you execute the logstash app, suppling your config file as input. The config file has a .conf suffix. So why does the LS Docker documentation talk about .yml files as config files? Are they the same?

Final Jeopardy Question: Once my config file is (hopefully) used, how do I verify Docker LS is running it?

Anyway, if you can see the error of my ways, I’d appreciate any help you can offer. Thanks!