Veeam 12 – SQL Log Backup Error: “Logs do not match any existing database backup

[mikkeland]

Hi all,

I’m running into an issue with SQL transaction log backups in Veeam and hoping someone can help clarify what I might be missing.

Environment:
* Veeam Backup & Replication v12 (latest)
* Nutanix AHV
* 1 × Microsoft SQL Server (likely 2019 or 2022)
* 6 online databases + several offline databases

Current setup:
* Backup job is fully functional
* Application-Aware Processing enabled
* Transaction log truncation working as expected
* Recently enabled periodic transaction log backups
* Performed a new full backup after enabling log backups

Issue:
Log backups are running and truncating logs, but I consistently get this error:

Code: Select all

Collected SQL Server transaction logs do not match any existing database backup

Relevant log snippet:

Code: Select all

[SqlLogApplicabilityChecker] Log chain for database [DBNAME] cannot be applied to a full backup
[14.04.2026 15:19:28.311]    <43>   Error (3)    [SqlLogApplicabilityChecker] Database backup: [Name=arcgis:InstanceName=:@first_LSN=14194000001969600037:@last_LSN=14194000001972800001:start_creation_time=02-04-2026 22:30:58:creation_usn=303]
[14.04.2026 15:19:28.311]    <43>   Error (3)    [SqlLogApplicabilityChecker] Prev log backup: [id=8363fd97-ec02-43b4-83a0-03108b47a9ee:guest_db_id=4b92cc3b-26dd-4e1e-a463-719397dc4dab:@first_LSN=14194000001976800001:@last_LSN=14200000002232000001:file_name={11ab91ec-6e2f-4dd4-bed7-38a079c91cb3}.bak:creation_usn=317]
[14.04.2026 15:19:28.311]    <43>   Error (3)    [SqlLogApplicabilityChecker] Next log backup: [id=8363fd97-ec02-43b4-83a0-03108b47a9ee:guest_db_id=4b92cc3b-26dd-4e1e-a463-719397dc4dab:@first_LSN=14194000001976800001:@last_LSN=14200000002232000001:file_name={11ab91ec-6e2f-4dd4-bed7-38a079c91cb3}.bak:creation_usn=317]
[14.04.2026 15:19:28.311]    <43>   Error (3)    [PrepareOperation] Log DBNAME cannot be applied

Observations:
* Log chain appears to be broken (LSNs don’t align between full and log backups)
* Veeam logs only reference **online databases** (as expected)
* Previous backups (before enabling log backups) used AAP with **truncation only**
* Restore points exist from before enabling periodic log backups

Question:
* After enabling periodic log backups and running a new full backup, I expected a clean log chain.
* Why would Veeam still report that the log backups don’t match an existing full backup?
* Is this expected behavior due to previous backup chains (pre-log-backup configuration)?
* As i have already done an active full, do I reset the chain in some way?

Any insights or similar experiences would be greatly appreciated.

Thanks in advance

[david.domask]

Hi mikkeland,

Please open a Support Case for the issue and let Veeam Support review the debug logs. All technical issues require a Support Case as noted when creating a topic, and topics on technical issues without a support case will be removed as per the forum rules.

Nothing about your setup seems incorrect at first blush, so it's best to check this in a support case. Your logic is correct, after enabling the log backups, a regular image level backup should be all that's necessary. (Hint btw: Active Full not required here, an incremental backup is fine. With Application Aware Processing and SQL Databases, all image level backups (full or incremental) are logical full SQL backups)

Please share your case number once created, thanks!