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--- title: Check the Last Sync Time property for a storage account titleSuffix: Azure Storage description: Learn how to check the Last Sync Time property for a geo-replicated storage account. The Last Sync Time property indicates the last time at which all writes from the primary region were successfully written to the secondary region. services: storage author: stevenmatthew ms.service: azure-storage ms.topic: how-to ms.date: 07/20/2023 ms.author: shaas ms.reviewer: artek ms.subservice: storage-common-concepts # Customer intent: As a cloud storage administrator, I want to check the Last Sync Time property for a geo-replicated storage account so that I can assess data consistency and evaluate potential data loss during an outage. --- # Check the Last Sync Time property for a storage account Geo-replication offers durability for your data, even during natural disasters and other significant outages in your primary region. When you configure a storage account, you can choose to have your data copied to a secondary region that is hundreds of miles from the primary region. In addition, you can choose to enable read access to the secondary region, ensuring that your data remains available for read operations if the primary region becomes unavailable. This approach enables you to [design your highly available application](../blobs/storage-create-geo-redundant-storage.md) to switch seamlessly to reading from the secondary region if the primary region is unresponsive. Geo-redundant storage (GRS) and geo-zone-redundant storage (GZRS) both replicate your data asynchronously to a secondary region. For read access to the secondary region, enable read-access geo-redundant storage (RA-GRS) or read-access geo-zone-redundant storage (RA-GZRS). For more information about the various options for redundancy offered by Azure Storage, see [Azure Storage redundancy](storage-redundancy.md). This article describes how to check the **Last Sync Time** property for your storage account so that you can evaluate any discrepancy between the primary and secondary regions. ## About the Last Sync Time property Because geo-replication is asynchronous, it's possible that data written to the primary region hasn't yet been written to the secondary region at the time an outage occurs. The **Last Sync Time** property indicates the most recent time that data from the primary region is guaranteed to have been written to the secondary region. For accounts that have a hierarchical namespace, the same **Last Sync Time** property also applies to the metadata managed by the hierarchical namespace, including ACLs. All data and metadata written prior to the last sync time is available on the secondary, while data and metadata written after the last sync time may not have been written to the secondary, and may be lost. Use this property in the event of an outage to estimate the amount of data loss you may incur by initiating a customer-managed (unplanned) failover. The **Last Sync Time** property is a GMT date/time value. ## Get the Last Sync Time property You can use PowerShell or Azure CLI to retrieve the value of the **Last Sync Time** property. # [PowerShell](#tab/azure-powershell) To get the last sync time for the storage account with PowerShell, install version 1.11.0 or later of the [Az.Storage](https://www.powershellgallery.com/packages/Az.Storage) module. Then check the storage account's **GeoReplicationStats.LastSyncTime** property. Remember to replace the placeholder values with your own values: ```powershell $lastSyncTime = $(Get-AzStorageAccount -ResourceGroupName <resource-group> ` -Name <storage-account> ` -IncludeGeoReplicationStats).GeoReplicationStats.LastSyncTime ``` # [Azure CLI](#tab/azure-cli) To get the last sync time for the storage account with Azure CLI, check the storage account's **geoReplicationStats.lastSyncTime** property. Use the `--expand` parameter to return values for the properties nested under **geoReplicationStats**. Remember to replace the placeholder values with your own values: ```azurecli-interactive $lastSyncTime=$(az storage account show \ --name <storage-account> \ --resource-group <resource-group> \ --expand geoReplicationStats \ --query geoReplicationStats.lastSyncTime \ --output tsv) ``` --- ## See also - [Azure Storage redundancy](storage-redundancy.md) - [Change the redundancy option for a storage account](redundancy-migration.md) - [Use geo-redundancy to design highly available applications](geo-redundant-design.md)