####Docker Docker is an open-source project that automates the deployment of applications inside software containers, by providing an additional layer of abstraction and automation of operating-system-level virtualization on Linux. https://www.docker.com/what-docker
####Dockerfiles for Fedora, Ubuntu and Centos The docker files, Dockerfile-fedora, Dockerfile-ubuntu, and Dockerfile-centos provide quick start docker containers with a running instance of qpid dispatch router on the various platforms.
The dockerfiles follow these steps before launching the dispatch router
####Building and running Dockerfiles
To build the fedora docker file
sudo docker build -t docker-image-name --file=Dockerfile-fedora . (substitute docker-image-name with your own image name)
To build the ubuntu docker file
sudo docker build -t docker-image-name --file=Dockerfile-ubuntu . (substitute docker-image-name with your own image name)
To build the centos docker file
sudo docker build -t docker-image-name --file=Dockerfile-centos . (substitute docker-image-name with your own image name)
To run the fedora/ubuntu/centos docker image
sudo docker run -i -t docker-image-name (substitute docker-image-name with your own image name)
After the docker run command is invoked, execute the sudo docker ps command to check if your container name shows up in the list of docker processes.
####Running unit tests Uncomment the line RUN ctest -VV to run the dispatch unit and system tests.
####Getting core dumps and backtraces from qdrouterd crashes and asserts
Install gdb. Add another step to the Docker build file and rebuild.
RUN dnf -y install gdb
Run the docker image shell prompt in a container with extended privileges
sudo docker run --privileged -i -t docker-image-name /bin/bash
At the container shell prompt enable crash dumps (as appropriate for your container host)
$ ulimit -c unlimited
$ echo “coredump.%e.%p” > /proc/sys/kernel/core_pattern
From the build directory run ctest
$ ctest -VV -R some_test
From the build directory examine core file in test setUpClass directory of the failed router. The core file is in the same directory as the router log file. The example shown here is for a policy oversize basic test failure while using the MaxMessageSizeBlockOversize class.
$ gdb router/qdrouterd ./tests/system_test.dir/system_tests_policy_oversize_basic/MaxMessageSizeBlockOversize/setUpClass/coredump.nnn.mmm
(gdb) bt
####Note These dockerfiles are provided for developers to quickly get started with the dispatch router and are not intended for use in production environments.