When using S3-compatible object storage on-prem the region ID can often be defined in the web interface of the solution, however, in some cases, it cannot be defined. When adding the storage either as an Unstructured Data source to be backed up or as an S3-target backup repository, it’s recommended to define the region value.
Especially in the case of backing up data, defining the wrong region can cause issues either during backup or restores.
If you are unsure, you can always review the Veeam Backup & Replication logs to see which region ID the storage is sending to Veeam.
You can find this information in the task log: C:\ProgramData\Veeam\Backup\jobname\bucketname\Task.bucket.log
[15.12.2025 13:10:03.372] <31> [000A] Info (3) [Agent] Setting creds to Amazon S3 REST, clientId: {3168C435-8BF9-40BE-8057-8C7355C1CDD9}, region: on-prem, connectionApiEndpoint: 192.168.102.88/
[15.12.2025 13:10:03.372] <31> [000A] Info (3) [AP] (aaa36282) command: 'Invoke: System.SetAmazonS3RestCredentials { (EString) ClientId = {3168C435-8BF9-40BE-8057-8C7355C1CDD9}; (EString) Region = on-prem; (EString) ApiUri = https://192.168.102.88; }'