Description

OpenShift manifests and instructions for running Azure Agent on OpenShift

Documentation

• running azure agent in Docker
• based on azure-pipelines-ephemeral-agents

Build Instructions

Customisations

• OpenShift Client Binary installed
• Automatic cleanup of agents on container exit
• ephermal agent runs a single job and then exits using --once
• enable proxy setting

Create azure-repos pull secret

# Create azure devops basic auth secret for accessing git repo
# replace <user_name> with your username
# replace <token> with the generated token from azure devops
oc create secret generic azure-repo-secret \
    --from-literal=username=<user_name> \
    --from-literal=password=<token> \
    --type=kubernetes.io/basic-auth

Create build config and imagestream

# Generate buildconfig and imagestream
 oc process -f manifests/azure-agent-buildconfig.yaml --param=GIT_URL=https://mocatad@dev.azure.com/mocatad/DNZ-269/_git/azure-devops-agent-openshift --param=REPO_SECRET=azure-repo-secret | oc apply -f -

Azure Agent Deployment

Create azure-agent configmap

#OpenShift cluster NOT running behind a proxy
oc process -f manifests/azure-agent-configmap.yaml \
    --param=AZP_URL='https://dev.azure.com/mocatad' \
    --param=AZP_POOL="Dev.Container" | oc apply -f -

#OpenShift cluster running behind a proxy
oc process -f manifests/azure-agent-configmap.yaml \
    --param=AZP_URL='https://dev.azure.com/mocatad' \
    --param=AZP_POOL="Dev.Container" \
    --param=HTTP_URL="http://myproxy:3128" \
    --param-HTTP_USERNAME="username to access process" | oc apply -f -

Create azure-agent secret with PAT

PAT can be generated as documented here or extraced from password store

#OpenShift cluster NOT running behind a proxy
oc process -f manifests/azure-agent-secret.yaml --param=AZP_TOKEN='<TOKEN>' | oc apply -f - 

#OpenShift cluster  running behind a proxy that requires a password
oc process -f manifests/azure-agent-secret.yaml \
    --param=AZP_TOKEN='<TOKEN>' \
    --param=PROXY_PASSWORD="mypassword" | oc apply -f - 

Deploy azure-devops-agent POD

# Defaults
oc process -f manifests/azure-agent-deployment.yaml --parameters=true
NAME                DESCRIPTION         GENERATOR           VALUE
IMAGE               Image to use                            azure-devops-agent:latest
CPU_LIMIT           CPU Limit                               200m
MEMORY_LIMIT        Memory limit                            300Mi

# Example
oc process -f manifests/azure-agent-deployment.yaml --param IMAGE=byroncollins/azure-devops-agent:latest | oc apply -f -

Scale agents

The Agents PODs deployed are designed to execute a single job and then exit and then OpenShift will spin up another POD to take over.

Running PODs with multi replicas can improve the availablity of the agents running in OpenShift.

oc scale deployment/azure-devops-agent --replicas=2

Deployment from Azure Pipelines

You can now execute Azure Pipeline jobs using your azure-agent running in the OpenShift Cluster

Access

Would recommend configuring a serviceaccount that your pipeline will use to authenticate on the Cluster. Creating a service account and assigning that service account "project admin" restricts what the service account can control

OpenShift Documentation

• Service Accounts
• Manage RBAC

Create project and service account

The service account could exist in the same project that you've created to run the azure agents

oc create -n azure-devops-agent serviceaccount azure-agent

Assign project admin role to namespaces

oc policy add-role-to-user admin -z azure-devops-agent

Retreve token

Tokens are generated automatically when the service account is created and are created as secrets

Delete the secrets to automatically regenerate

oc describe sa/azure-devops-agent
Name:                azure-devops-agent
Namespace:           azure-devops-agent
Labels:              <none>
Annotations:         <none>
Image pull secrets:  azure-devops-agent-dockercfg-28g22
Mountable secrets:   azure-devops-agent-token-cp46z
                     azure-devops-agent-dockercfg-28g22
Tokens:              azure-devops-agent-token-cp46z
                     azure-devops-agent-token-f5hzv
Events:              <none>

oc get secrets azure-devops-agent-token-f5hzv

You could store the token in an azure vault to be accessible from azure-pipelines

Don't forget that the secret is in base64 format and needs to be decrypted before using or storing.