Merge pull request #36653 from MicrosoftDocs/main

Auto Publish – main to live - 2026-02-19 18:30 UTC

Author: learn-build-service-prod[bot]

azure-sql/database/high-availability-sla-local-zone-redundancy.md

@@ -49,7 +49,7 @@ There are three availability architectural models:
 - **Local storage model** that is based on a cluster of database engine processes. The local storage model relies on the fact that there's always a quorum of available database engine nodes. This architecture targets mission-critical applications with high IO performance, high transaction rate and guarantees minimal performance impact on your workload during maintenance activities.
 - **Hyperscale model** which uses a distributed system of highly available components such as compute nodes, page servers, log service, and persistent storage. Each component supporting a Hyperscale database provides its own redundancy and resiliency to failures. Compute nodes, page servers, and log service run on Azure Service Fabric, which controls health of each component and performs failovers to available healthy nodes as necessary. Persistent storage uses Azure Storage with its native high availability and redundancy capabilities. To learn more, see [Hyperscale architecture](hyperscale-architecture.md).
 
-Within each of the three availability models, SQL Database supports local redundancy and zonal redundancy options. Local redundancy provides resiliency within a datacenter, while zonal redundancy improves resiliency further by protecting against outages of an availability zone within a region.
+Within each of the three availability models, SQL Database supports local redundancy and zone redundancy options. Local redundancy provides resiliency within a datacenter, while zone redundancy improves resiliency further by protecting against outages of an availability zone within a region.
 
 The following table shows the availability options based on service tiers:
 
@@ -229,7 +229,7 @@ Consider the following limitations:
 
 In Azure SQL Database, a [server](logical-servers.md) is a logical construct that acts as a central administrative point for a collection of databases. At the server level, you can administer logins, authentication method, firewall rules, auditing rules, threat detection policies, and failover groups. Data related to some of these features, such as logins and firewall rules, is stored in the `master` database. Similarly, data for some DMVs, for example [sys.resource_stats](/sql/relational-databases/system-catalog-views/sys-resource-stats-azure-sql-database), is also stored in the `master` database.
 
-When a database with a zone-redundant configuration is created on a logical server, the `master` database associated with the server is automatically made zone-redundant as well. This ensures that in a zonal outage, applications using the database remain unaffected because features dependent on the `master` database, such as logins and firewall rules, are still available. Making the `master` database zone-redundant is an asynchronous process and will take some time to finish in the background.
+When a database with a zone-redundant configuration is created on a logical server, the `master` database associated with the server is automatically made zone-redundant as well. This ensures that in a zone outage, applications using the database remain unaffected because features dependent on the `master` database, such as logins and firewall rules, are still available. Making the `master` database zone-redundant is an asynchronous process and will take some time to finish in the background.
 
 When none of the databases on a server are zone-redundant, or when you create an empty server, then the `master` database associated with the server is **not zone-redundant**. To migrate your Azure SQL Database to use zone redundancy, follow the steps in [Migrate Azure SQL Database to availability zone support](enable-zone-redundancy.md).
 

docs/sql-server/azure-arc/troubleshoot-deployment.md

@@ -44,7 +44,7 @@ If you can't see it, the extension didn't install properly. Try the following st
 
 1. Check event logs to see if anything preventing installation. Try installing SqlServerExtension.msi from the following folder `C:\Packages\Plugins\Microsoft.AzureData.WindowsAgent.SqlServer{version}`. The installation UI may provide the error details.
 
-2. Close services app, server manager and retry one of the [connection methods](./connect.md) to install the extension, and see if that helps.
+2. Close services app, server manager and retry using [connection method](./connect-already-enabled.md) to install the extension, and see if that helps.
 
 ## Extension installed but didn't start
 

docs/sql-server/sql-server-2025-known-issues.md

@@ -4,7 +4,7 @@ description: Known issues, causes, and workarounds for SQL Server 2025 (17.x), c
 author: MikeRayMSFT
 ms.author: mikeray
 ms.reviewer: randolphwest
-ms.date: 02/11/2026
+ms.date: 02/18/2026
 ms.service: sql
 ms.subservice: release-landing
 ms.topic: troubleshooting-known-issue
@@ -36,6 +36,7 @@ The following issues are currently identified:
 - [Upgrade fails if Data Quality Services is installed](#upgrade-fails-if-data-quality-services-is-installed)
 - [Full-Text Search fails to index plaintext documents larger than 25 MB](#full-text-search-fails-to-index-plaintext-documents-larger-than-25-mb)
 - [Incorrect license agreement for LocalDB installer](#incorrect-license-agreement-for-localdb-installer)
+- [SQL Server might become slow or unresponsive after creating or bringing online a large number of databases](#sql-server-might-become-slow-or-unresponsive-after-creating-or-bringing-online-a-large-number-of-databases)
 
 ## SQL Server 2025 installation fails when TLS 1.2 is disabled
 
@@ -210,6 +211,14 @@ To work around this issue, you must download the Express edition installer inste
 
 We have identified a fix for a future release of [!INCLUDE [sssql25-md](../includes/sssql25-md.md)].
 
+## SQL Server might become slow or unresponsive after creating or bringing online a large number of databases
+
+**Issue**: This behavior is caused by a per database background worker thread created as part of the [Persisted statistics for readable secondary replicas](../relational-databases/performance/persisted-stats-secondary-replicas.md) feature. This feature is enabled by default in [!INCLUDE [sssql25-md](../includes/sssql25-md.md)]. The background thread is created when databases come online and can cause worker thread pressure and reduced instance responsiveness, even when no secondary replicas are configured.
+
+**Workaround**: Enable startup [trace flag 15608](../t-sql/database-console-commands/dbcc-traceon-trace-flags-transact-sql.md#tf15608) and restart [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)]. You must enable the trace flag at startup. Enabling it after startup doesn't stop background threads that are already created for databases that were brought online. In scenarios with no secondary replicas, this trace flag is still required as a temporary mitigation to prevent the per database background thread from being created during database startup.
+
+A fix is planned for a future update of [!INCLUDE [sssql25-md](../includes/sssql25-md.md)].
+
 ## Related content
 
 - [What's new in SQL Server 2025](what-s-new-in-sql-server-2025.md)