Add Jetstack Helm repository
| Platform | Comando |
|---|---|
| kubectl (Static Manifests) | kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.13.3/cert-manager.yaml |
| Helm (Recommended) | helm install cert-manager jetstack/cert-manager --namespace cert-manager --create-namespace --set installCRDs=true |
| macOS (cmctl CLI) | brew install cmctl |
| Linux (cmctl CLI) | `curl -sSL https://github.com/cert-manager/cert-manager/releases/download/v1.13.3/cmctl-linux-amd64.tar.gz \ |
| Windows (cmctl CLI) | curl.exe -L -o cmctl.exe https://github.com/cert-manager/cert-manager/releases/download/v1.13.3/cmctl-windows-amd64.exe |
| Verify Installation | kubectl get pods -n cert-manager |
# Add Jetstack Helm repository
helm repo add jetstack https://charts.jetstack.io
# Update repository
helm repo update
# Install with custom values
helm install cert-manager jetstack/cert-manager \
--namespace cert-manager \
--create-namespace \
--version v1.13.3 \
--values custom-values.yaml
```## Instalación
| Comando | Descripción |
|---------|-------------|
| `kubectl get certificates` | Listar todos los certificados en el espacio de nombres actual |
| `kubectl get certificates -A` | Listar certificados en todos los namespaces |
| `kubectl describe certificate <name>` | Mostrar información detallada del certificado |
| `kubectl get certificate <name> -o yaml` | Ver certificado en formato YAML |
| `kubectl get issuer` | Listar todos los emisores en el espacio de nombres actual |
| `kubectl get clusterissuer` | Enumerar todos los emisores de clúster |
| `kubectl describe issuer <name>` | Mostrar información detallada del emisor |
| `kubectl get certificaterequest` | Listar solicitudes de certificado |
| `kubectl get order` | Ver pedidos de certificados ACME |
| `kubectl get challenge` | Ver desafíos ACME para validación de dominio |
| `kubectl logs -n cert-manager deployment/cert-manager` | Ver registros del controlador cert-manager |
| `kubectl logs -n cert-manager deployment/cert-manager-webhook` | Ver registros de webhook |
| `kubectl logs -n cert-manager deployment/cert-manager-cainjector` | Ver logs del inyector CA |
| `cmctl check api` | Verificar que la API de cert-manager esté disponible |
| `cmctl version` | Mostrar información de versión de cert-manager |
| `cmctl status certificate <name>` | Verificar estado y preparación del certificado |
| `cmctl inspect secret <secret-name>` | Inspeccionar secreto TLS creado por cert-manager |
| `cmctl renew <cert-name>` | Activar manualmente la renovación de certificado |
| `kubectl get crd \ | grep cert-manager` | Enumerar todas las Definiciones de Recursos Personalizados (Custom Resource Definitions) de cert-manager |
| `kubectl get events --field-selector involvedObject.name=<cert-name>` | Ver eventos relacionados con un certificado específico |### Configuración del Repositorio Helm
| Comando | Descripción |
|---------|-------------|
| `cmctl approve <certificaterequest-name>` | Aprobar manualmente una solicitud de certificado |
| `cmctl deny <certificaterequest-name>` | Denegar una solicitud de certificado |
| `cmctl create certificaterequest test --from-certificate-file=cert.yaml` | Crear solicitud de certificado desde archivo |
| `cmctl convert --output-format=pem --input-file=cert.yaml` | Convertir certificado a formato PEM |
| `cmctl experimental create acmeaccount --server=<url> --email=<email>` | Registro de cuenta ACME de prueba |
| `kubectl annotate certificate <name> cert-manager.io/issue-temporary-certificate="true" --overwrite` | Forzar renovación inmediata de certificado |
| `kubectl delete certificaterequest <name>` | Eliminar solicitud de certificado fallida |
| `kubectl delete order <name>` | Eliminar orden de ACME |
| `kubectl delete challenge <name>` | Eliminar desafío ACME atascado |
| `kubectl get certificate <name> -o jsonpath='{.status.conditions}'` | Extraer condiciones de estado de certificado |
| `kubectl get secret <tls-secret> -o jsonpath='{.data.tls\.crt}' \ | base64 -d \ | openssl x509 -text -noout` | Decodificar y ver detalles del certificado |
| `kubectl get secret <tls-secret> -o jsonpath='{.data.tls\.crt}' \ | base64 -d \ | openssl x509 -noout -dates` | Verificar fechas de expiración de certificados |
| `helm upgrade cert-manager jetstack/cert-manager --namespace cert-manager --version v1.13.3` | Actualizar cert-manager a nueva versión |
| `kubectl rollout restart deployment -n cert-manager` | Reiniciar todos los componentes de cert-manager |
| `kubectl scale deployment cert-manager -n cert-manager --replicas=2` | Escalar cert-manager para alta disponibilidad |
| `kubectl get certificate --watch` | Ver cambios de estado de certificados en tiempo real |
| `kubectl patch certificate <name> --type merge -p '{"spec":{"renewBefore":"720h"}}'` | Modificar ventana de renovación de certificado |
| `kubectl delete secret <tls-secret>` | Eliminar secreto de certificado (desencadena recreación) |
| `cmctl experimental install` | Instalar cert-manager usando la herramienta cmctl |
| `cmctl experimental uninstall` | Desinstalar cert-manager y limpiar recursos |
```yaml
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: selfsigned-issuer
spec:
selfSigned: {}
```## Comandos Básicos
```yaml
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: letsencrypt-staging
spec:
acme:
server: https://acme-staging-v02.api.letsencrypt.org/directory
email: admin@example.com
privateKeySecretRef:
name: letsencrypt-staging
solvers:
- http01:
ingress:
class: nginx
```## Uso Avanzado
```yaml
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: letsencrypt-prod
spec:
acme:
server: https://acme-v02.api.letsencrypt.org/directory
email: admin@example.com
privateKeySecretRef:
name: letsencrypt-prod
solvers:
- dns01:
cloudDNS:
project: my-gcp-project
serviceAccountSecretRef:
name: clouddns-dns01-solver
key: key.json
```## Configuración
```yaml
apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
name: ca-issuer
namespace: default
spec:
ca:
secretName: ca-key-pair
```### ClusterIssuer Autofirmado
```yaml
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: example-com
namespace: default
spec:
secretName: example-com-tls
issuerRef:
name: letsencrypt-prod
kind: ClusterIssuer
dnsNames:
- example.com
- www.example.com
duration: 2160h # 90 days
renewBefore: 360h # 15 days before expiry
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: wildcard-cert
namespace: default
spec:
secretName: wildcard-tls
issuerRef:
name: letsencrypt-prod
kind: ClusterIssuer
dnsNames:
- "*.example.com"
- example.com
```### Let's Encrypt Staging (Desafío HTTP-01)
```yaml
apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
name: vault-issuer
namespace: default
spec:
vault:
server: https://vault.example.com
path: pki/sign/example-dot-com
auth:
kubernetes:
mountPath: /v1/auth/kubernetes
role: cert-manager
secretRef:
name: vault-token
key: token
# custom-values.yaml
installCRDs: true
replicaCount: 2
resources:
requests:
cpu: 100m
memory: 128Mi
limits:
cpu: 200m
memory: 256Mi
prometheus:
enabled: true
servicemonitor:
enabled: true
webhook:
replicaCount: 2
cainjector:
replicaCount: 2
```### Let's Encrypt Producción (Desafío DNS-01)
```bash
# Create ClusterIssuer
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: letsencrypt-prod
spec:
acme:
server: https://acme-v02.api.letsencrypt.org/directory
email: admin@example.com
privateKeySecretRef:
name: letsencrypt-prod
solvers:
- http01:
ingress:
class: nginx
EOF
# Create Ingress with TLS annotation
kubectl apply -f - <<EOF
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: example-ingress
annotations:
cert-manager.io/cluster-issuer: "letsencrypt-prod"
spec:
ingressClassName: nginx
tls:
- hosts:
- example.com
secretName: example-com-tls
rules:
- host: example.com
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: example-service
port:
number: 80
EOF
# Verify certificate creation
kubectl get certificate
kubectl describe certificate example-com-tls
# Create self-signed CA
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: selfsigned-issuer
spec:
selfSigned: {}
---
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: my-ca
namespace: cert-manager
spec:
isCA: true
commonName: my-ca
secretName: my-ca-secret
privateKey:
algorithm: ECDSA
size: 256
issuerRef:
name: selfsigned-issuer
kind: ClusterIssuer
EOF
# Create CA issuer from generated CA
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: my-ca-issuer
spec:
ca:
secretName: my-ca-secret
EOF
# Issue service certificates
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: service-a-cert
namespace: default
spec:
secretName: service-a-tls
duration: 8760h
renewBefore: 720h
subject:
organizations:
- my-org
commonName: service-a.default.svc.cluster.local
dnsNames:
- service-a.default.svc.cluster.local
issuerRef:
name: my-ca-issuer
kind: ClusterIssuer
EOF
```### Emisor de CA (PKI Interno)
```bash
# Create DNS provider secret (example: Cloudflare)
kubectl create secret generic cloudflare-api-token \
--from-literal=api-token=YOUR_CLOUDFLARE_API_TOKEN
# Create ClusterIssuer with DNS-01 solver
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: letsencrypt-dns
spec:
acme:
server: https://acme-v02.api.letsencrypt.org/directory
email: admin@example.com
privateKeySecretRef:
name: letsencrypt-dns
solvers:
- dns01:
cloudflare:
email: admin@example.com
apiTokenSecretRef:
name: cloudflare-api-token
key: api-token
EOF
# Request wildcard certificate
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: wildcard-example
namespace: default
spec:
secretName: wildcard-example-tls
issuerRef:
name: letsencrypt-dns
kind: ClusterIssuer
dnsNames:
- "*.example.com"
- example.com
EOF
# Monitor certificate issuance
kubectl get certificate wildcard-example -w
# Create certificate for webhook
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: webhook-cert
namespace: webhook-system
spec:
secretName: webhook-server-cert
duration: 8760h
renewBefore: 720h
issuerRef:
name: selfsigned-issuer
kind: ClusterIssuer
dnsNames:
- webhook-service.webhook-system.svc
- webhook-service.webhook-system.svc.cluster.local
EOF
# Reference in webhook configuration
kubectl apply -f - <<EOF
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingWebhookConfiguration
metadata:
name: my-webhook
annotations:
cert-manager.io/inject-ca-from: webhook-system/webhook-cert
webhooks:
- name: webhook.example.com
clientConfig:
service:
name: webhook-service
namespace: webhook-system
path: "/validate"
caBundle: "" # Injected by cert-manager
EOF
```### Recurso de Certificado
```bash
# Create certificate with short duration for testing
kubectl apply -f - <<EOF
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: short-lived-cert
namespace: default
spec:
secretName: short-lived-tls
duration: 24h
renewBefore: 8h
issuerRef:
name: selfsigned-issuer
kind: ClusterIssuer
dnsNames:
- test.example.com
EOF
# Monitor renewal
kubectl get certificate short-lived-cert -w
# Force immediate renewal
kubectl annotate certificate short-lived-cert \
cert-manager.io/issue-temporary-certificate="true" \
--overwrite
# Check renewal history
kubectl get certificaterequest -l cert-manager.io/certificate-name=short-lived-cert
# Verify new certificate
cmctl inspect secret short-lived-tls
renewBefore### Certificado Wildcard
certmanager_certificate_expiration_timestamp_seconds
-
Usar DNS-01 para wildcards y servicios internos: El desafío DNS-01 es necesario para certificados wildcard y funciona mejor para servicios no expuestos a internet
-
Implementar RBAC adecuado: Restringir el acceso a Issuers y secretos de certificados usando Kubernetes RBAC para prevenir la creación de certificados no autorizados
-
Versionar configuraciones: Almacenar manifiestos de Certificate e Issuer en Git para rastrear cambios y habilitar flujos de trabajo GitOps
-
Usar issuers separados por entorno: Crear diferentes issuers para desarrollo/staging/producción para aislar credenciales y prevenir problemas de certificados entre entornos
-
Habilitar inyección de CA para webhooks: Usar
cert-manager.io/inject-ca-fromannotation para inyectar automáticamente paquetes CA en configuraciones de webhook
| Problema | Solución |
|---|---|
| Certificate stuck in “Pending” | Check certificate request: kubectl describe certificaterequest <name>. Look for ACME challenge failures or issuer configuration errors |
| ACME HTTP-01 challenge failing | Verify ingress is accessible: curl http://<domain>/.well-known/acme-challenge/test. Check ingress class matches solver configuration |
| DNS-01 challenge timeout | Confirm DNS provider credentials: kubectl get secret <dns-secret> -o yaml. Verify DNS propagation: dig TXT _acme-challenge.<domain> |
| ”Too many certificates” rate limit | Cambie al servidor de pruebas de Let’s Encrypt o espere 7 días. Verifique los límites de tasa: https://letsencrypt.org/docs/rate-limits/ |
| Certificate not renewing automatically | Check renewBefore setting and cert-manager logs: kubectl logs -n cert-manager deployment/cert-manager. Verify controller is running |
| Webhook connection failures | Verify webhook service is running: kubectl get svc -n cert-manager. Check webhook certificate validity: cmctl check api |
| CA injection not working | Ensure cainjector is running: kubectl get pods -n cert-manager. Verify annotation syntax: cert-manager.io/inject-ca-from: namespace/certificate |
| Certificate shows “Ready=False” | Get detailed status: cmctl status certificate <name>. Check events: kubectl get events --field-selector involvedObject.name=<cert-name> |
| Order stuck in “Pending” | Delete order to retry: kubectl delete order <order-name>. Certificate controller will create new order automatically |
| Secret not created after certificate ready | Check secret name matches secretName in Certificate spec. Verify namespace: kubectl get secret <name> -n <namespace> |
| Wildcard certificate validation fails | Asegúrese de que el solucionador DNS-01 esté configurado (HTTP-01 no admite comodines). Verifique los permisos del proveedor DNS para la creación de registros TXT |
| Certificate shows wrong issuer | Delete certificate request: kubectl delete certificaterequest <name>. Update Certificate spec with correct issuerRef |
| High memory usage | Reduce certificate count or increase resources: kubectl set resources deployment cert-manager -n cert-manager --limits=memory=512Mi |
| Duplicate certificates created | Check for multiple Certificate resources with same secretName. Remove duplicates to prevent conflicts |
| ACME account registration fails | Verificar formato de correo electrónico en la especificación del emisor. Comprobar que la URL del servidor ACME sea correcta. Revisar los registros de cert-manager para obtener mensajes de error detallados |
Resolución de problemas
# Complete troubleshooting workflow
kubectl describe certificate <cert-name>
kubectl get certificaterequest -l cert-manager.io/certificate-name=<cert-name>
kubectl describe certificaterequest <request-name>
kubectl get order
kubectl describe order <order-name>
kubectl get challenge
kubectl describe challenge <challenge-name>
kubectl logs -n cert-manager deployment/cert-manager --tail=100
```### Secuencia de Comandos de Depuración
```bash
# Search for specific certificate errors
kubectl logs -n cert-manager deployment/cert-manager | grep "certificate=<cert-name>"
# Find ACME challenge errors
kubectl logs -n cert-manager deployment/cert-manager | grep "challenge"
# Check for rate limit errors
kubectl logs -n cert-manager deployment/cert-manager | grep "rate limit"
# Monitor certificate renewal attempts
kubectl logs -n cert-manager deployment/cert-manager -f | grep "renewal"