AB#6855 hyper-v-replica-troubleshooting-guide.md

Author: v-lianna

support/windows-server/toc.yml

@@ -2744,6 +2744,8 @@ items:
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     - name: Feature and performance optimization of HVR
       href: ./virtualization/feature-performance-optimization-hyper-v-replica.md
+    - name: Hyper-V Replica troubleshooting guide
+      href: ./virtualization/hyper-v-replica-troubleshooting-guide.md
   - name: Installation and configuration of Hyper-V
     items:
     - name: Antivirus exclusions for Hyper-V hosts

support/windows-server/virtualization/hyper-v-replica-troubleshooting-guide.md

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+---
+title: Hyper-V Replica Troubleshooting Guide
+description: Helps consolidate real-world failure scenarios, symptoms, root causes, and step-by-step resolutions to assist administrators in diagnosing and resolving Hyper-V Replica issues in both standalone and clustered deployments.
+ms.date: 08/08/2025
+manager: dcscontentpm
+audience: itpro
+ms.topic: troubleshooting
+ms.reviewer: kaushika, jeffhuge, v-lianna
+ms.custom:
+- sap:virtualization and hyper-v\hyper-v replica (hvr)
+- pcy:WinComm Storage High Avail
+---
+# Hyper-V Replica Troubleshooting Guide: Common Failure Modes, Causes, and Resolutions
+
+Hyper-V Replica is an essential feature for disaster recovery and business continuity in Windows Server environments. It enables asynchronous replication of virtual machines (VMs) between primary and secondary sites. However, due to its complex integration with clusters, networks, authentication, storage, and security policies, various issues can arise. These issues may stem from configuration errors, permission problems, network instability, VM version mismatches, or software defects. This guide consolidates real-world failure scenarios, symptoms, root causes, and step-by-step resolutions to assist administrators in diagnosing and resolving Hyper-V Replica issues in both standalone and clustered deployments.
+
+## Symptoms
+
+### End-user experience
+
+* Inability to enable, resume, or remove Hyper-V replication for one or more virtual machines.
+* Replication health states displayed as "Critical," "Paused," or "Resynchronization Required."
+* Virtual machines unexpectedly shutting down or becoming unavailable.
+
+### Technical/system symptoms
+
+* Replication is stuck at 1%, paused, or not progressing.
+* The Replica Broker or Replica role fails to come online in a cluster.
+* Replicated virtual machines do not receive updates after the initial sync.
+* Virtual machine migration (Live Migration or Quick Migration) fails.
+* Replication cannot be enabled or deleted; commands hang or produce errors.
+* Virtual Machine Management Service (VMMS) is stuck in a stopping state, or VMs are stuck in the “Applying Replication changes” state.
+* Disk space on the primary host fills up rapidly due to growing differencing (HRL) files.
+* Replication fails after an operating system upgrade or patching.
+
+### Error messages and event IDs
+
+Common error messages include:
+
+* "Hyper-V failed to authenticate the replica server using Kerberos authentication. Error: the connect with the server was terminated abnormally (0x00002EFE)."
+* "Enabling replication failed. The parameter is incorrect. (0x80070057)."
+* "Hyper-V operation failed because the specified parameter is not valid. IncludedDisks is not valid for Hyper-V operation for virtual machine."
+* "Hyper-V could not replicate changes for virtual machine…The system cannot find the file specified. (0x80070002)."
+* "Resume-VMReplication: Could not change the replication state. Virtual machine is not in a valid replication state to perform the operation."
+* "Hyper-V Replica Broker failed to register the service principal name: The user name or password is incorrect. (0x8007052E)."
+
+Frequent event IDs include:
+32022, 33680, 32086, 29286, 32000, 32090, 32315, 21102, 33824, 33826, 21502, 20100, 32552, 153, 51, 55, 1193, 1194.
+
+## Cause
+
+### 1\. Network and authentication issues
+
+* Inadequate network bandwidth or unstable network connections.
+* Incorrect firewall or port settings blocking required traffic (default port: 443 for HTTPS).
+* Errors in Kerberos or certificate-based authentication configurations.
+* Domain trust issues or misconfigured service principal names (SPNs).
+
+### 2\. Configuration errors
+
+* Incorrect settings for initial replication or the Replica Broker role in clustered environments.
+* Mismatched virtual machine configurations between primary and replica sites.
+* Insufficient disk space or incompatible storage configurations.
+
+### 3\. Permissions and security
+
+* Lack of appropriate administrative permissions for Hyper-V Replica setup.
+* Misconfigured NTFS permissions or storage access controls.
+* Security software or policies interfering with replication traffic.
+
+### 4\. Software or hardware issues
+
+* Incompatibility between Hyper-V Replica versions after updates or patches.
+* Corruption of differencing files or HRL files.
+* Hardware failures affecting disk or network components.
+
+## Resolution
+
+### Step 1: Validate network connectivity
+
+* Ensure that the primary and replica servers can communicate over the required ports (443 for HTTPS).
+* Check for and resolve any network latency or instability issues.
+
+### Step 2: Verify authentication settings
+
+* Confirm that Kerberos authentication or certificate-based authentication is correctly configured.
+* Ensure SPNs are registered properly for the Hyper-V Replica Broker in a cluster.
+
+### Step 3: Check configuration settings
+
+* Verify that initial replication, scheduling, and retention settings are correct.
+* Confirm that the Replica Broker role is properly configured in clustered deployments.
+* Ensure that the storage paths on the primary and replica servers are accessible and have sufficient space.
+
+### Step 4: Address permissions and security
+
+* Grant the necessary administrative permissions to the accounts used for replication.
+* Review and adjust NTFS permissions to ensure proper access for replication-related files.
+* Disable or reconfigure antivirus or security software that may block Hyper-V Replica traffic.
+
+### Step 5: Resolve software or hardware issues
+
+* Reapply updates or patches