---
title: "include file"
description: "include file"
services: storage
author: stevenmatthew
ms.service: azure-storage
ms.subservice: common-concepts
ms.topic: "include"
ms.date: 08/04/2024
ms.author: shaas
ms.custom: "include file", references_regions
---
Important
After a planned failover, a storage account's Last Sync Time (LST) value might appear stale or be reported as NULL when Azure Files data is present.
System snapshots are periodically created in a storage account's secondary region to maintain consistent recovery points used during failover and failback. Initiating customer-managed planned failover causes the original primary region to become the new secondary. In some cases, there are no system snapshots available on the new secondary after the planned failover completes, causing the account's overall LST value to appear stale or be displayed as Null.
Because user activities such as creating, modifying, or deleting objects can trigger snapshot creation, any account on which these activities occur after planned failover will not require additional attention. However, accounts having no snapshots or user activity may continue to display a Null LST value until system snapshot creation is triggered.
If necessary, perform one of the following activities for each share within a storage account to trigger snapshot creation. Upon completion, your account should display a valid LST value within 30 minutes' time.
- Mount the share, then open any file for reading.
- Upload a test or sample file to the share.