Cert-Manager
🛡️ Cert-Manager: SSL Certificates Management in Kubernetes
Cert-Manager is a powerful tool for automating the management of ssl-certs within Kubernetes clusters. This guide provides an overview of Cert-Manager’s features, focuses on self-signed certificate creation, and addresses common troubleshooting issues.
🔍 Overview
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Cert-Manager is an SSL certificates management tool that automates the creation, renewal, and management of SSL certificates within a Kubernetes environment.
Product Type: SSL Certificates Manager
Focus: Automating SSL certificate creation, renewal, and management within Kubernetes.
Key Uses: Automating SSL certificates management, including creation, renewal, and troubleshooting in Kubernetes clusters.
🧠 Key Features of Cert-Manager
Cert-Manager offers a range of features for managing SSL certificates in Kubernetes:
🧑💻 SSL Certificate Automation
[!tip]
Cert-Manager automates the creation, renewal, and management of SSL certificates in a Kubernetes environment, reducing manual work.
🛠️ Multiple Issuer Support
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Cert-Manager supports different types of issuers, including self-signed certificates, internal CA certificates, and external certificate authorities, offering flexibility in certificate management.
🗂️ Customizable Issuer Configuration
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You can configure theIssuer
andClusterIssuer
resources to manage certificates based on different policies and certificate authorities, providing control over your certificate management process.
🌍 Certificate Challenges
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Cert-Manager supports different types of challenges like HTTP-01, DNS-01, and more to validate the ownership of domain names for certificate issuance.
📊 Certificate Renewal
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Cert-Manager automatically renews certificates before they expire, ensuring continuous SSL protection without manual intervention.
🌍 Explore More
For further reading and detailed guides, check out the official Cert-Manager documentation: Cert-Manager Docs.
🚨 Common Issues and Troubleshooting
🧩 Self-Signed Certificates Creation
Option 1: Upload Existing CA.key and CA.crt Files
Create a Self-Signed CA
Generate the private key (ca.key):
openssl genrsa -out ca.key 4096
Generate the certificate (ca.crt):
openssl req -new -x509 -sha256 -days 365 -key ca.key -out ca.crt
Convert the Files to Base64 String
Use
base64
to encode theca.key
andca.crt
files:cat ca.key | base64 -w 0
Create SSL Secret Object
Create a Kubernetes Secret with the base64-decoded values:
apiVersion: v1 kind: Secret metadata: name: ssl-issuer-secret type: Opaque data: tls.crt: <base64-decoded-string> tls.key: <base64-decoded-string>
Create the ClusterIssuer or Issuer Object
Use the Secret to configure a
ClusterIssuer
:apiVersion: cert-manager.io/v1 kind: ClusterIssuer metadata: name: selfsigned-issuer spec: ca: secretName: ssl-issuer-secret
Option 2: Create CA Through Cert-Manager
Create the ClusterIssuer or Issuer Object Using the
selfSigned
AttributeUse Cert-Manager’s built-in functionality to create a self-signed certificate:
apiVersion: cert-manager.io/v1 kind: ClusterIssuer metadata: name: root-issuer spec: selfSigned: {}
⚠️ Common Errors and Solutions
DNS Record Not Yet Propagated
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Error:Waiting for DNS-01 challenge propagation: DNS record for "your-dns-record" not yet propagated.
Cause: DNS records (TXT records) may not have propagated yet, which is required for Cert-Manager to issue the certificate.
Solution: Configure DNS to use external resolvers:
```yaml
extraArgs:
- --dns01-recursive-nameservers-only
- --dns01-recursive-nameservers=8.8.8.8:53,1.1.1.1:53
```
No Solver Found
[!error]
Error:Failed to determine a valid solver configuration for the set of domains on the Order: no configured challenge solvers can be used for this challenge
Cause: Missing or misconfigured solver settings for handling the DNS challenge.
Solution: Ensure that thednsZones
in your solver configuration match the DNS hostnames zone.
📚 Further Information
For more in-depth guides, configuration details, and troubleshooting tips, refer to the official Cert-Manager documentation:
🔁 Related Resources
[!info]
SSL Certificates and Security Tools — Explore other SSL-related tools and best practices.
Kubernetes Networking — Learn more about networking in Kubernetes and integrating security solutions.
🏷️ Tags
#cert-manager
#ssl-certs
#kubernetes
#self-signed-certificates
#dns
#network-security
#kubernetes-management
#certificate-automation
#tls-certs