1. Our environment:
Veeam Backup & Replication (Advanced edition), HPE MSL3040 tape library, LTO-9 SAS HH drives, Windows Server 2025. Source data lives on a NAS file share (accessed via SMB/NFS). Processed data gets written to tape via a File to Tape job.
2. Our requirement — tape verification:
We need our verification to cover two layers:
Read-after-write — checking tape parity and block integrity as blocks are written by the tape drive head, to ensure physical tape sectors have no write errors.
Content integrity — after writing, reading back the raw file structures from tape, generating a cryptographic MD5 checksum of that data, and matching it against the original source file's MD5 to confirm the two are identical.
Ideally this would be something we can run as part of an automated job rather than a manual step.
3. Why this matters:
Once a file is archived to tape, the source copy gets deleted from the NAS share to reclaim space. That means tape becomes the only copy — there's no going back to the source to re-verify or re-copy if something's wrong after the fact. We need full confidence in the tape content before that deletion happens, not after.
4. Tape mirroring:
We also want two independent tape copies of the same data for redundancy. What are our options for achieving this in Veeam — and how do they compare in terms of drive time, license requirements, and behavior on repeated/incremental runs?
What we have found so far, and where we are stuck:
Read-after-write appears to be inherent to the LTO drive hardware — always on, nothing to configure — but this only confirms the physical write, not that content matches the original source file.
Start-VBRTapeVerification re-reads tape and checks against checksums the drive wrote at backup time — this confirms tape readability, not a source-vs-tape content match.
Getting the actual MD5-vs-source comparison seems to require pulling file content back off tape via the tape restore cmdlets, which Veeam's PowerShell reference flags as obsolete, recommending the UI instead for full functionality.
For anyone running an archive-then-delete workflow where tape becomes the sole copy — is there a supported, scriptable way to get a true source-vs-tape MD5 verification? And what's the right approach for dual-tape redundancy in this kind of setup? Any real-world patterns (especially ones that have held up to an audit) would help a lot.
