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DevOps-Security-Agent-Skills/devops/orchestration/openshift/SKILL.md
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2026-01-27 17:35:45 -05:00
---
name: openshift
description: Manage Red Hat OpenShift clusters and deployments. Configure projects, routes, builds, and deploy applications using OpenShift-specific features. Use when working with OpenShift Container Platform or OKD for enterprise Kubernetes.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# OpenShift
Deploy and manage applications on Red Hat OpenShift Container Platform.
## When to Use This Skill
Use this skill when:
- Deploying applications to OpenShift clusters
- Using OpenShift-specific features (Routes, BuildConfigs)
- Managing projects and RBAC in OpenShift
- Implementing S2I (Source-to-Image) builds
- Working with OpenShift Operators
## Prerequisites
- OpenShift cluster access
- oc CLI installed
- Basic Kubernetes knowledge
## CLI Basics
### Authentication
```bash
# Login to cluster
oc login https://api.cluster.example.com:6443 -u admin -p password
# Login with token
oc login --token=sha256~xxxx --server=https://api.cluster.example.com:6443
# Check current context
oc whoami
oc whoami --show-server
oc whoami --show-context
# Logout
oc logout
```
### Project Management
```bash
# Create project (namespace)
oc new-project myapp --display-name="My App" --description="My Application"
# Switch project
oc project myapp
# List projects
oc projects
# Delete project
oc delete project myapp
```
## Deploying Applications
### From Image
```bash
# Deploy from container image
oc new-app --image=nginx:latest --name=webserver
# Deploy from Docker Hub
oc new-app docker.io/library/nginx:latest
# Deploy with environment variables
oc new-app myimage:latest \
-e DATABASE_URL=postgres://localhost/db \
-e APP_ENV=production
```
### From Source (S2I)
```bash
# Deploy from Git repository
oc new-app https://github.com/org/myapp.git
# Specify builder image
oc new-app nodejs:18~https://github.com/org/nodejs-app.git
# With context directory
oc new-app https://github.com/org/monorepo.git \
--context-dir=backend \
--name=backend-api
```
### From Template
```bash
# List available templates
oc get templates -n openshift
# Deploy from template
oc new-app postgresql-persistent \
-p POSTGRESQL_USER=user \
-p POSTGRESQL_PASSWORD=secret \
-p POSTGRESQL_DATABASE=mydb
```
## Routes
### Creating Routes
```yaml
apiVersion: route.openshift.io/v1
kind: Route
metadata:
name: myapp
spec:
host: myapp.apps.cluster.example.com
to:
kind: Service
name: myapp
weight: 100
port:
targetPort: 8080
tls:
termination: edge
insecureEdgeTerminationPolicy: Redirect
```
```bash
# Create route via CLI
oc expose svc/myapp
# Create with custom hostname
oc create route edge myapp \
--service=myapp \
--hostname=myapp.apps.cluster.example.com
# Create passthrough route (TLS termination at pod)
oc create route passthrough myapp-secure --service=myapp
```
### A/B Testing
```yaml
apiVersion: route.openshift.io/v1
kind: Route
metadata:
name: myapp
spec:
to:
kind: Service
name: myapp-v1
weight: 90
alternateBackends:
- kind: Service
name: myapp-v2
weight: 10
```
## Build Configurations
### BuildConfig
```yaml
apiVersion: build.openshift.io/v1
kind: BuildConfig
metadata:
name: myapp
spec:
source:
type: Git
git:
uri: https://github.com/org/myapp.git
ref: main
strategy:
type: Docker
dockerStrategy:
dockerfilePath: Dockerfile
output:
to:
kind: ImageStreamTag
name: myapp:latest
triggers:
- type: ConfigChange
- type: GitHub
github:
secret: webhook-secret
```
### S2I Build
```yaml
apiVersion: build.openshift.io/v1
kind: BuildConfig
metadata:
name: myapp
spec:
source:
type: Git
git:
uri: https://github.com/org/myapp.git
strategy:
type: Source
sourceStrategy:
from:
kind: ImageStreamTag
namespace: openshift
name: nodejs:18-ubi8
env:
- name: NPM_RUN
value: start
output:
to:
kind: ImageStreamTag
name: myapp:latest
```
### Build Commands
```bash
# Start build
oc start-build myapp
# Start build from local source
oc start-build myapp --from-dir=.
# Follow build logs
oc start-build myapp --follow
# View build logs
oc logs -f bc/myapp
# Cancel build
oc cancel-build myapp-1
```
## Image Streams
```yaml
apiVersion: image.openshift.io/v1
kind: ImageStream
metadata:
name: myapp
spec:
lookupPolicy:
local: true
tags:
- name: latest
from:
kind: DockerImage
name: registry.example.com/myapp:latest
importPolicy:
scheduled: true
```
```bash
# Create image stream
oc create imagestream myapp
# Import image
oc import-image myapp:latest \
--from=docker.io/library/nginx:latest \
--confirm
# Tag image
oc tag myapp:latest myapp:production
```
## Deployment Configs
```yaml
apiVersion: apps.openshift.io/v1
kind: DeploymentConfig
metadata:
name: myapp
spec:
replicas: 3
selector:
app: myapp
template:
metadata:
labels:
app: myapp
spec:
containers:
- name: myapp
image: myapp:latest
ports:
- containerPort: 8080
resources:
requests:
memory: "128Mi"
cpu: "100m"
limits:
memory: "256Mi"
cpu: "500m"
triggers:
- type: ConfigChange
- type: ImageChange
imageChangeParams:
automatic: true
containerNames:
- myapp
from:
kind: ImageStreamTag
name: myapp:latest
strategy:
type: Rolling
rollingParams:
maxSurge: 25%
maxUnavailable: 25%
```
## ConfigMaps and Secrets
```bash
# Create ConfigMap
oc create configmap myapp-config \
--from-literal=APP_ENV=production \
--from-file=config.yaml
# Create Secret
oc create secret generic myapp-secrets \
--from-literal=password=secret123
# Mount as volume
oc set volume dc/myapp \
--add --name=config \
--type=configmap \
--configmap-name=myapp-config \
--mount-path=/etc/config
# Set as environment
oc set env dc/myapp --from=secret/myapp-secrets
```
## Security Context Constraints
```bash
# List SCCs
oc get scc
# View SCC details
oc describe scc restricted
# Grant SCC to service account
oc adm policy add-scc-to-user anyuid -z myapp-sa -n myproject
# Create service account
oc create serviceaccount myapp-sa
```
### Custom SCC
```yaml
apiVersion: security.openshift.io/v1
kind: SecurityContextConstraints
metadata:
name: myapp-scc
allowPrivilegedContainer: false
runAsUser:
type: MustRunAsNonRoot
seLinuxContext:
type: MustRunAs
fsGroup:
type: RunAsAny
volumes:
- configMap
- secret
- persistentVolumeClaim
users:
- system:serviceaccount:myproject:myapp-sa
```
## Operators
```bash
# List available operators
oc get packagemanifests -n openshift-marketplace
# Subscribe to operator
cat <<EOF | oc apply -f -
apiVersion: operators.coreos.com/v1alpha1
kind: Subscription
metadata:
name: prometheus
namespace: openshift-operators
spec:
channel: stable
name: prometheus
source: community-operators
sourceNamespace: openshift-marketplace
EOF
# View installed operators
oc get csv -n openshift-operators
```
## Monitoring
```bash
# View pod logs
oc logs -f pod/myapp-1-xyz
# View events
oc get events --sort-by='.lastTimestamp'
# Resource usage
oc adm top pods
oc adm top nodes
# Debug pod
oc debug pod/myapp-1-xyz
```
## Common Issues
### Issue: Build Fails
**Problem**: S2I build cannot find dependencies
**Solution**: Check builder image, verify source repository access
### Issue: Pod Security Violation
**Problem**: Pod fails to start due to SCC
**Solution**: Use appropriate SCC or modify container security context
### Issue: Route Not Working
**Problem**: Cannot access application via route
**Solution**: Verify service selector, check router pods, validate DNS
### Issue: Image Pull Error
**Problem**: Cannot pull image from registry
**Solution**: Create image pull secret, link to service account
```bash
oc create secret docker-registry regcred \
--docker-server=registry.example.com \
--docker-username=user \
--docker-password=pass
oc secrets link default regcred --for=pull
```
## Best Practices
- Use Projects for isolation (not just namespaces)
- Leverage ImageStreams for image management
- Use BuildConfigs for CI/CD integration
- Implement proper SCCs (avoid privileged)
- Use Routes instead of Ingress
- Leverage OpenShift templates for repeatability
- Monitor with built-in Prometheus
- Use Operators for complex applications
## Related Skills
- [kubernetes-ops](../kubernetes-ops/) - K8s fundamentals
- [helm-charts](../helm-charts/) - Helm deployments
- [container-registries](../../containers/container-registries/) - Image management