Yes, Microsoft CA (AD CS) can be integrated with MTG CLM. This allows you to continue using your existing Microsoft CA while extending its use to cross-platform, non-Windows-specific use cases, such as issuing Linux server certificates via ACME.
For companies that already operate a Microsoft PKI, there are two practical options:
Professional Package: Your Microsoft PKI remains in operation while MTG CLM manages the certificate-based processes. This enables centralized certificate management and automation.
Ultimate Package: When the CLM Autoenrollment Connector is used as part of the Ultimate Package, Microsoft PKI can be replaced by MTG PKI while established Active Directory-based autoenrollment processes continue to be used.
These options allow you to benefit from modern PKI and CLM capabilities while either retaining your existing infrastructure or migrating to MTG PKI.