| Cause | Description | Typical Environment |
|-------|-------------|---------------------|
| Large number of restore points | More than 1,000 restore points for a single VM, causing integer overflow in internal counters. | Long-term GFS retention. |
| Corrupted catalog / metadata | Malformed index or CBT (Changed Block Tracking) data leading to buffer overflow. | After improper shutdown, storage latency, or snapshot issues. |
| SQL database limitations | Veeam configuration DB runs out of int space for job_history_id or similar identity columns. | Very old Veeam installations (upgraded from version <9.5) with millions of log records. |
| Very long object names | VM name, disk name, or backup file path exceeds 255 characters, overflowing a varchar column. | Multi-cloud, nested folders, or long SAN LUN names. |
| 32-bit service components | Older Veeam agents or mount services using 32-bit memory addressing (max 2–4 GB). | Mixed-mode backups with legacy physical servers. |
In computing, an overflow occurs when a program tries to store a value that is too large for the designated memory space or variable type. In the context of Veeam Backup and Replication, this error manifests in several ways, including:
The error is not a hardware failure per se, but rather a data inconsistency problem—often tied to Veeam’s configuration database (SQL Server or PostgreSQL), log files exceeding expected limits, or corrupted metadata from a backup chain.
Check your exact Veeam build number (Help > About). For known overflow issues:
Always test in a non-production environment first.
Third-party VSS writers on a guest VM (like SQL Server or Exchange) may pass unusual metadata sizes to Veeam. A VSS writer reporting a dwEstimatedSize value of FFFFFFFF (hex) can trigger an overflow in the Veeam VSS requestor.
During replication, Veeam tracks VM disk sectors changed since last sync. If the change tracking bitmap exceeds its allocated memory buffer (especially with thin-provisioned disks > 64TB), an overflow occurs.