Dockerfile Best Practices

OpenShift on CentOS 7
OpenShift ''Getting Started'' on GitHub
Create builder images with S2I

DNS for OpenShift v3 cluster
OpenShift 3.6 Master Node config
Sudhaker's blog

• Packages needed:
  • yum install go
  • Install S2I from: https://github.com/openshift/source-to-image/releases
• ?

# Gen image via s2i ... using python container
IMGBASE=s2i-python-container
mkdir s2iloadgen
s2i create ${IMGBASE} s2iloadgen

• List all Bluejay-related images:

  docker images | grep -i bluejay

• Start container:

  docker run -d -P --name loadgen001 bluejay-loadgen

• Show port mapping:

  docker port loadgen001 22

• Stop container:

  docker container stop loadgen001

• Remove container:

  docker container rm loadgen001

• Remove image:

  docker image rm bluejay-loadgen

• In /etc/yum.repos.d/docker.repo

  [dockerrepo]
  name=Docker Repository
  baseurl=https://yum.dockerproject.org/repo/main/centos/7
  enabled=1
  gpgcheck=1
  gpgkey=https://yum.dockerproject.org/gpg

• yum install docker-engine
• usermod -aG docker msamud1
• chkconfig docker on
• Install S2I: download and extract to /usr/local/bin …

  wget https://github.com/openshift/source-to-image/releases/download/v1.1.10/source-to-image-v1.1.10-27f0729d-linux-amd64.tar.gz

• OpenShift CLI client (oc):
  • Requires active RHEL subscription to download
  • Once downloaded, extract “oc” from archive into /usr/local/bin

http://www.testautomationguru.com/jmeter-distributed-load-testing-using-docker/
https://hub.docker.com/_/openjdk/
https://eleanordare.com/blog/2018/5/3/using-a-jenkins-pipeline-to-run-jmeter-tests-in-openshift-bkba6
https://eleanordare.com/blog/2017/6/14/using-a-jenkins-pipeline-to-run-jmeter-tests-in-openshift
https://blog.openshift.com/remotely-push-pull-container-images-openshift
https://docs.openshift.org/latest/dev_guide/jobs.html
https://docs.openshift.com/enterprise/3.0/architecture/core_concepts/builds_and_image_streams.html
https://blog.openshift.com/running-any-docker-image-on-openshift-origin/
https://docs.openshift.com/online/architecture/core_concepts/builds_and_image_streams.html#pipeline-build
https://docs.openshift.com/online/dev_guide/application_lifecycle/new_app.html#dev-guide-new-app
https://docs.openshift.com/online/dev_guide/index.html
https://docs.openshift.com/online/dev_guide/builds/build_inputs.html#image-source
https://docs.openshift.com/online/dev_guide/application_lifecycle/new_app.html
https://blog.openshift.com/getting-any-docker-image-running-in-your-own-openshift-cluster/
https://blog.openshift.com/openshift-jobs
https://docs.openshift.com/online/rest_api/apis-batch/v1.Job.html

• Ensure that docker-engine is installed on Linux XaaS VM
• Log in to DTR (Docker Trusted Registry)
  docker login docker.optum.com
• Pull existing repository (previously created in web GUI)
  docker pull docker.optum.com/msamud1/bluejay-jmeter
• Build new image using S2I (S2I build is another topic)
• Tag new image in local registry
  docker tag <newimageid> docker.optum.com/msamud1/bluejay-jmeter
• Push to DTR
  docker push docker.optum.com/msamud1/bluejay-jmeter

NOTE: these commands assume being run from $HOME/src/bluejay …
* Log in to Optum's OpenShift (this is elk river non-prod)
oc login https://ocp-elr-core-nonprod.optum.com * Create image stream for base JMeter builder image
oc create -f ./etc/jmeter.yaml * Create image stream for app-specific load controller
oc create -f ./etc/timbrado.json * Create image stream for load generator(s)
oc create -f ./etc/loadgen.json * Create BuildConfig for app-specific load controller
oc create -f ./etc/bld-timbrado.json * Create BuildConfig for load generator(s)
oc create -f ./etc/bld-loadgen.json * Run a job:
oc create -f ./etc/job-launch.yaml ===== Misc … ===== ==== Container DNS ==== In order for containers to be able to resolve external names, change the dnsIP value in /var/lib/origin/openshift.local.config/node-localhost/node-config.yaml to the real LAN's DNS nameserver
==== SSH Key Initialization ==== <code> /usr/bin/ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key -N /usr/bin/ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N /usr/bin/ssh-keygen -t ecdsa -f /etc/ssh/ssh_host_ecdsa_key -N /usr/bin/ssh-keygen -t ed25519 -f /etc/ssh/ssh_host_ed25519_key -N /usr/bin/ssh-keygen -A </code> ==== Interesting Resources ==== * https://hub.docker.com/r/jdeathe/centos-ssh
Links … Tech … Linux