You can install multiple SSL certificates on a server for different domain names or subdomains. The number of certificates that can be installed varies based on the actual scenario. The following list describes the scenarios in which you can configure multiple certificates for a server:
Multi-domain hosting: If a server hosts multiple websites, and each website has an independent domain name, you must configure a certificate for each domain name to ensure that each domain name can provide secure HTTPS access.
Numerous subdomains: In a large-sized enterprise or organization, a large number of subdomains may be used in different departments, projects, or services. To provide separate HTTPS protection for each subdomain, you must configure a certificate for each important subdomain. Alternatively, you can use a wildcard certificate, such as a certificate bound to
*.example.com, to all subdomains of the same top-level domain. If specific subdomains have special requirements, such as requiring specific information for organization validation, you must separately install certificates for the subdomains.Multi-service or multi-application deployment: In a microservices architecture or containerized environment, a server may run multiple independent services or applications. Each service provides an HTTPS API by using a unique domain name or port. To ensure the security of communication between each service and the security of connections between clients and the service, you must deploy a certificate for the domain name of each service.
In actual business scenarios, to simplify certificate management and reduce risks such as service interruptions caused by certificate expiration and update failure, we recommend that you reduce the number of certificates installed on a server. In most cases, a multi-domain or wildcard certificate is used to implement HTTPS for multiple domain names.