rudironsoni dotnet-container-deployment
Deploying .NET containers to Kubernetes and local development environments. Covers Kubernetes Deployment + Service + probe YAML, Docker Compose for local dev workflows, and CI/CD integration for building and pushing container images.
Scope
- Kubernetes Deployment, Service, and probe YAML for .NET apps
- Docker Compose for local development workflows
- CI/CD integration for building and pushing container images
Out of scope
- Dockerfile authoring, multi-stage builds, and base image selection -- see [skill:dotnet-containers]
- Advanced CI/CD pipeline patterns (matrix builds, deploy pipelines) -- see [skill:dotnet-gha-deploy] and [skill:dotnet-ado-patterns]
- DI and async patterns -- see [skill:dotnet-csharp-dependency-injection] and [skill:dotnet-csharp-async-patterns]
- Testing container deployments -- see [skill:dotnet-integration-testing] and [skill:dotnet-playwright]
Cross-references: [skill:dotnet-containers] for Dockerfile and image best practices, [skill:dotnet-observability] for health check endpoint patterns used by Kubernetes probes.
Kubernetes Deployment
Deployment Manifest
A production-ready Kubernetes Deployment for a .NET API:
apiVersion: apps/v1
kind: Deployment
metadata:
name: order-api
labels:
app: order-api
app.kubernetes.io/name: order-api
app.kubernetes.io/version: '1.0.0'
app.kubernetes.io/component: api
spec:
replicas: 3
selector:
matchLabels:
app: order-api
template:
metadata:
labels:
app: order-api
spec:
containers:
- name: order-api
image: ghcr.io/myorg/order-api:1.0.0
ports:
- containerPort: 8080
protocol: TCP
env:
- name: ASPNETCORE_ENVIRONMENT
value: 'Production'
- name: OTEL_EXPORTER_OTLP_ENDPOINT
value: 'http://otel-collector.monitoring:4317'
- name: OTEL_SERVICE_NAME
value: 'order-api'
- name: ConnectionStrings__DefaultConnection
valueFrom:
secretKeyRef:
name: order-api-secrets
key: connection-string
resources:
requests:
cpu: '100m'
memory: '128Mi'
limits:
cpu: '500m'
memory: '512Mi'
livenessProbe:
httpGet:
path: /health/live
port: 8080
initialDelaySeconds: 10
periodSeconds: 15
timeoutSeconds: 3
failureThreshold: 3
readinessProbe:
httpGet:
path: /health/ready
port: 8080
initialDelaySeconds: 5
periodSeconds: 10
timeoutSeconds: 3
failureThreshold: 3
startupProbe:
httpGet:
path: /health/live
port: 8080
initialDelaySeconds: 0
periodSeconds: 5
failureThreshold: 30
securityContext:
runAsNonRoot: true
runAsUser: 1654
fsGroup: 1654
terminationGracePeriodSeconds: 30
```text
### Service Manifest
Expose the Deployment within the cluster:
```yaml
apiVersion: v1
kind: Service
metadata:
name: order-api
labels:
app: order-api
spec:
type: ClusterIP
selector:
app: order-api
ports:
- port: 80
targetPort: 8080
protocol: TCP
name: http
```text
### ConfigMap for Non-Sensitive Configuration
```yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: order-api-config
data:
ASPNETCORE_ENVIRONMENT: 'Production'
Logging__LogLevel__Default: 'Information'
Logging__LogLevel__Microsoft.AspNetCore: 'Warning'
```text
Reference in the Deployment:
```yaml
envFrom:
- configMapRef:
name: order-api-config
```yaml
### Secrets for Sensitive Configuration
```yaml
apiVersion: v1
kind: Secret
metadata:
name: order-api-secrets
type: Opaque
stringData:
connection-string: 'Host=postgres;Database=orders;Username=app;Password=<DB_PASSWORD_PLACEHOLDER>'
```text
In production, use an external secrets operator (e.g., External Secrets Operator, Sealed Secrets) rather than plain
Kubernetes Secrets stored in source control.
---
## Kubernetes Probes
Probes tell Kubernetes how to check application health. They map to the health check endpoints defined in your .NET
application (see [skill:dotnet-observability]).
### Probe Types
| Probe | Purpose | Endpoint | Failure Action |
| ------------- | ---------------------------------- | --------------- | ------------------------------------------------------- |
| **Startup** | Has the app finished initializing? | `/health/live` | Keep waiting (up to `failureThreshold * periodSeconds`) |
| **Liveness** | Is the process healthy? | `/health/live` | Restart the pod |
| **Readiness** | Can the process serve traffic? | `/health/ready` | Remove from Service endpoints |
### Probe Configuration Guidelines
```yaml
# Startup probe: give the app time to initialize
# Total startup budget: failureThreshold * periodSeconds = 30 * 5 = 150s
startupProbe:
httpGet:
path: /health/live
port: 8080
initialDelaySeconds: 0
periodSeconds: 5
failureThreshold: 30
# Liveness probe: detect deadlocks and hangs
# Only runs after startup probe succeeds
livenessProbe:
httpGet:
path: /health/live
port: 8080
periodSeconds: 15
timeoutSeconds: 3
failureThreshold: 3
# Readiness probe: control traffic routing
readinessProbe:
httpGet:
path: /health/ready
port: 8080
periodSeconds: 10
timeoutSeconds: 3
failureThreshold: 3
```text
### Graceful Shutdown
.NET responds to `SIGTERM` and begins graceful shutdown. Configure `terminationGracePeriodSeconds` to allow in-flight
requests to complete:
```yaml
spec:
terminationGracePeriodSeconds: 30
```yaml
In your application, use `IHostApplicationLifetime` to handle shutdown:
```csharp
app.Lifetime.ApplicationStopping.Register(() =>
{
// Perform cleanup: flush telemetry, close connections
Log.CloseAndFlush();
});
```text
Ensure the `Host.ShutdownTimeout` allows in-flight requests to complete:
```csharp
builder.Host.ConfigureHostOptions(options =>
{
options.ShutdownTimeout = TimeSpan.FromSeconds(25);
});
```text
Set `ShutdownTimeout` to a value less than `terminationGracePeriodSeconds` to ensure the app shuts down before
Kubernetes sends `SIGKILL`.
---
## Docker Compose for Local Development
Docker Compose provides a local development environment that mirrors production dependencies.
### Basic Compose File
```yaml
# docker-compose.yml
services:
order-api:
build:
context: .
dockerfile: src/OrderApi/Dockerfile
ports:
- '8080:8080'
environment:
- ASPNETCORE_ENVIRONMENT=Development
- ConnectionStrings__DefaultConnection=Host=postgres;Database=orders;Username=app;Password=<DB_PASSWORD_PLACEHOLDER>
- OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4317
depends_on:
postgres:
condition: service_healthy
redis:
condition: service_healthy
# Note: CMD-SHELL + curl requires a base image with shell and curl installed.
# Chiseled/distroless images lack both. For chiseled images, either use a
# non-chiseled dev target in the Dockerfile or omit the healthcheck and rely
# on depends_on ordering (acceptable for local dev).
healthcheck:
test: ['CMD-SHELL', 'curl -f http://localhost:8080/health/live || exit 1']
interval: 10s
timeout: 3s
retries: 3
start_period: 10s
postgres:
image: postgres:17
environment:
POSTGRES_DB: orders
POSTGRES_USER: app
POSTGRES_PASSWORD: devpassword
ports:
- '5432:5432'
volumes:
- postgres-data:/var/lib/postgresql/data
healthcheck:
test: ['CMD-SHELL', 'pg_isready -U app -d orders']
interval: 5s
timeout: 3s
retries: 5
redis:
image: redis:7-alpine
ports:
- '6379:6379'
healthcheck:
test: ['CMD', 'redis-cli', 'ping']
interval: 5s
timeout: 3s
retries: 5
volumes:
postgres-data:
```text
### Development Override
Use a separate override file for development-specific settings:
```yaml
# docker-compose.override.yml (auto-loaded by docker compose up)
services:
order-api:
build:
target: build # Stop at build stage for faster rebuilds
volumes:
- .:/src # Mount source for hot reload
environment:
- ASPNETCORE_ENVIRONMENT=Development
- DOTNET_USE_POLLING_FILE_WATCHER=true
command: ['dotnet', 'watch', 'run', '--project', 'src/OrderApi/OrderApi.csproj']
```bash
### Observability Stack
Add an OpenTelemetry collector and Grafana for local observability:
```yaml
# docker-compose.observability.yml
services:
otel-collector:
image: otel/opentelemetry-collector-contrib:latest
command: ['--config=/etc/otelcol-config.yaml']
volumes:
- ./infra/otelcol-config.yaml:/etc/otelcol-config.yaml
ports:
- '4317:4317' # OTLP gRPC
- '4318:4318' # OTLP HTTP
grafana:
image: grafana/grafana:latest
ports:
- '3000:3000'
volumes:
- grafana-data:/var/lib/grafana
volumes:
grafana-data:
```text
## Detailed Examples
See [references/detailed-examples.md](references/detailed-examples.md) for complete code samples and advanced patterns.