@Pravendra Rajput , Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
How to set up incremental backups in azure file share and what needs to be changed in the backup policy?
Yes Azure File Share support Azure Incremental Back up. You can refer to this article, How to Setup Azure File Share Backup
Share snapshots are incremental in nature. Only the data that has changed after your most recent share snapshot is saved. This minimizes the time required to create the share snapshot and saves on storage costs.
https://learn.microsoft.com/en-us/azure/storage/files/storage-snapshots-files#space-usage
About Azure file share backup
Questions about backing up Azure Files
Share snapshots are incremental in nature. Only the data that has changed after your most recent share snapshot is saved. This minimizes the time required to create the share snapshot and saves on storage costs.
https://learn.microsoft.com/en-us/azure/storage/files/storage-snapshots-files#space-usage
If you have any additional questions or need further clarification, please let me know.
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