Document MSDTC limitations on SQL Server for Linux (#36830)

Added limitations regarding MSDTC support on Linux, including restrictions on distributed transactions and clustered configurations.

Author: AttinderPalSingh

docs/linux/sql-server-linux-configure-msdtc.md

@@ -3,7 +3,7 @@ title: How to Configure MSDTC on Linux
 description: In this article, learn how to configure the Microsoft Distributed Transaction Coordinator (MSDTC) on Linux.
 author: rwestMSFT
 ms.author: randolphwest
-ms.date: 01/02/2026
+ms.date: 03/16/2026
 ms.service: sql
 ms.subservice: linux
 ms.topic: how-to
@@ -49,15 +49,15 @@ For more information, see [Understanding XA Transactions](../connect/jdbc/unders
 
 Complete the following three steps to configure MSDTC communication and functionality for [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)].
 
-- Configure `network.rpcport` and `distributedtransaction.servertcpport` with **mssql-conf**.
+- Use **mssql-conf** to configure `network.rpcport` and `distributedtransaction.servertcpport`.
 - Configure the firewall to allow communication on `distributedtransaction.servertcpport` and port 135.
 - Configure Linux server routing so that RPC communication on port 135 is redirected to the [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)] instance's `network.rpcport`.
 
 The following sections provide detailed instructions for each step.
 
 ## Configure RPC and MSDTC ports
 
-Configure `network.rpcport` and `distributedtransaction.servertcpport` with **mssql-conf**. This step is specific to [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)] and common across all supported distributions.
+Use **mssql-conf** to configure `network.rpcport` and `distributedtransaction.servertcpport`. This step applies to [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)] and is common across all supported distributions.
 
 1. Use **mssql-conf** to set the `network.rpcport` value. The following example sets it to 13500.
 
@@ -148,9 +148,9 @@ Ubuntu and SLES don't use the **firewalld** service, so **iptables** rules are a
    > [!NOTE]  
    > You must have super user (sudo) privileges to edit the `rc.local` or `after.local` files.
 
-The `iptables-save` and `iptables-restore` commands, along with `rc.local`/`after.local` startup configuration, provide a basic mechanism to save and restore **iptables** entries. Depending on your Linux distribution, there might be more advanced or automated options available. For example, an Ubuntu alternative is the `iptables-persistent` package to make entries persistent.
+The `iptables-save` and `iptables-restore` commands, along with `rc.local`/`after.local` startup configuration, provide a basic mechanism to save and restore **iptables** entries. Depending on your Linux distribution, you might have more advanced or automated options available. For example, an Ubuntu alternative is the `iptables-persistent` package to make entries persistent.
 
-The previous steps assume a fixed IP address. If the IP address for your [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)] instance changes (due to manual intervention or DHCP), you must remove and recreate the routing rules if you created them with **iptables**. If you need to recreate or delete existing routing rules, use the following command to remove old `RpcEndPointMapper` rules:
+The previous steps assume a fixed IP address. If the IP address for your [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)] instance changes (due to manual intervention or DHCP), you must remove and recreate the routing rules if you created them with **iptables**. To recreate or delete existing routing rules, use the following command to remove old `RpcEndPointMapper` rules:
 
 ```bash
 sudo iptables -S -t nat | grep "RpcEndPointMapper" | sed 's/^-A //' | while read rule; do iptables -t nat -D $rule; done
@@ -215,6 +215,16 @@ If a client on a Windows operating system needs to enlist into distributed trans
 | [Windows Server](/windows-server/get-started/windows-server-release-info) | 1903 | 18362.30.190401-1528 |
 | [Windows 10](/windows/release-information/) | 1903 | 18362.267 |
 
+### Limitations
+
+- Distributed transactions support only standalone SQL Server instances. They don't support high-availability clustering.
+
+- MSDTC isn't supported with Always On availability groups on Linux, regardless of cluster type (`CLUSTER_TYPE = NONE` or `CLUSTER_TYPE = EXTERNAL`).
+
+- Coordinating distributed transactions across availability group replicas isn't supported. Handling distributed transactions during availability group failover scenarios isn't supported.
+
+- Clustered MSDTC configurations aren't supported on Linux.
+
 ## Related content
 
 - [What is SQL Server on Linux?](sql-server-linux-overview.md)