If you want to remove it from the domain it is just like removing any Windows server from the domain via the server properties.
In regards to offsite storage we support CIFS/SMB, Windows & Linux servers and dedupe devices. A NAS will work fine if it fits your company needs.
In regards to tape storage and our integration. We support LTO3 and newer. All you need to do is add a tape server and on that tape server install the drivers from the specific vendor's tape device (HPE, IBM,...). We have an unofficial list with supported devices: tape-f29/unofficial-tape-library-compatibility-list-t17488.html
- however most will work fine. If there are no Windows drivers by a specific vendor we can leverage native Windows SCSI commands to copy the data. For more information have a look at our userguide (https://helpcenter.veeam.com/backup/vsp ... _jobs.html