Merge pull request #219738 from mepand/patch-49

Update backup-afs.md

Author: prmerger-automator[bot]

articles/backup/backup-afs.md

@@ -24,6 +24,7 @@ In this article, you'll learn how to:
 * [Learn](azure-file-share-backup-overview.md) about the Azure file share snapshot-based backup solution.
 * Ensure that the file share is present in one of the [supported storage account types](azure-file-share-support-matrix.md).
 * Identify or create a [Recovery Services vault](#create-a-recovery-services-vault) in the same region and subscription as the storage account that hosts the file share.
+* In case you have restricted access to your storage account, check the firewall settings of the account to ensure that the exception "Allow Azure services on the trusted services list to access this storage account" is granted. You can refer to [this](../storage/common/storage-network-security.md?tabs=azure-portal#manage-exceptions) link for the steps to grant an exception.
 
 [!INCLUDE [How to create a Recovery Services vault](../../includes/backup-create-rs-vault.md)]