Does SSLcat support wildcard certificates?

Yes, SSLcat fully supports wildcard certificates. Wildcard certificates can cover all subdomains under a domain, greatly simplifying certificate management.

What are wildcard certificates

Wildcard certificates are a special type of SSL certificate:

• Format - Uses * wildcard, like *.example.com
• Coverage - Covers all first-level subdomains
• Not included - Does not include the main domain itself
• Validation method - Must use DNS validation

Advantages of wildcard certificates

Benefits of using wildcard certificates:

• Simplified management - One certificate manages multiple subdomains
• Cost reduction - Reduces certificate application and management costs
• Automated operations - Easier to implement automated deployment
• Good scalability - No need to reapply certificates for new subdomains

Supported domain formats

Domain formats supported by wildcard certificates:

• *.example.com - Covers all first-level subdomains
• *.api.example.com - Covers all subdomains under api
• *.dev.example.com - Covers all subdomains under dev

DNS validation configuration

Wildcard certificates must use DNS validation:

# Configuration example
certificates:
  - domain: "*.example.com"
    validation: "dns"
    dns_provider: "cloudflare"  # DNS provider
    dns_credentials:
      api_token: "your-api-token"

  - domain: "*.api.example.com"
    validation: "dns"
    dns_provider: "route53"
    dns_credentials:
      access_key: "your-access-key"
      secret_key: "your-secret-key"

Supported DNS providers

SSLcat supports multiple DNS providers:

• Cloudflare - Uses API Token
• Route53 - Uses AWS credentials
• Aliyun - Uses AccessKey
• Tencent Cloud - Uses SecretId/SecretKey
• DNSPod - Uses API Token
• Custom - Supports custom DNS scripts

Application process

The application process for wildcard certificates:

1. Configure DNS credentials - Set DNS provider credentials in the configuration file
2. Apply for certificate - Apply through admin panel or command line
3. DNS validation - Automatically create DNS records for validation
4. Certificate issuance - Let's Encrypt issues the certificate
5. Auto-installation - Automatically install to server

Usage example

Example of using wildcard certificates:

# Forwarding configuration
proxies:
  - domain: "www.example.com"
    target: "http://localhost:3000"
    certificate: "*.example.com"

  - domain: "api.example.com"
    target: "http://localhost:8080"
    certificate: "*.example.com"

  - domain: "admin.example.com"
    target: "http://localhost:9000"
    certificate: "*.example.com"

Important notes

Important considerations when using wildcard certificates:

• DNS permissions - DNS management permissions required
• Validation time - DNS validation may take several minutes
• Main domain - Main domain needs separate certificate application
• Multi-level subdomains - Multi-level wildcards not supported

Best practices

Best practices for wildcard certificates:

• Proper planning - Plan domain structure based on business needs
• Secure storage - Securely store DNS credentials
• Regular updates - Regularly update DNS credentials
• Monitoring alerts - Configure certificate expiration alerts

Wildcard certificates are the ideal choice for managing multiple subdomains, especially suitable for microservice architectures and SaaS applications.