Some months ago, last year to be precisely, it was on a Synology event, I saw a video that mentioned that DSM 7 will bring a new Active Directory package that will give us the possibility to set up a secondary domain controller (SDC), obviously on a second capable diskstation. Do not use Cloudstation Backup or Synology Drive Backup. Support for TLS domain controller certification. Synology directory server vs active directory server Rackmount NAS - Newegg.