Frequently asked questions about high availability (HA)
Last modified date:
2025-09-04
Applicable Models
App and Feature Compatibility
- App Compatibility List for High Availability Environments
- Which QuTS hero features are currently not supported in high availability mode?
- Why can't I see certain apps in App Center after configuring a high availability (HA) environment on my QNAP device?
Setup Requirements
- Can I create an HA cluster using two different NAS models?
- Can I enable HA with two NAS devices of the same model but different memory configurations?
- Can I enable HA with two NAS devices of the same model but different CPU configurations?
- Can I use UPS while HA is enabled?
- Why can't both NAS devices be active nodes in an HA cluster?
- Why are most features unavailable on the passive node of an HA cluster?
Cluster Creation
- How do I create a high-availability cluster?
- What is a cluster IP address and how do I use it?
- What is a cluster connection and how do I select an appropriate network interface for it?
- What is a heartbeat connection and how do I select an appropriate network interface for it?
- How do I choose the heartbeat interface for an HA cluster?
- Why can't I select certain network interfaces when creating an HA cluster?
- How do I configure port trunking for an HA cluster?
- What is a quorum server and how does it help my HA cluster?
- How long do HA initial synchronization, failover, and switchover take?
- How can I reduce initial synchronization time for my HA cluster?
HA Maintenance
- How can I test HA cluster functionality?
- When does failover occur in an HA cluster?
- What is split-brain and how do I recover?
- How do I verify and reconcile data after choosing 'Preserve data on both nodes' in a split-brain scenario?
- What should I do if downloading stops after a failover or switchover?
- How do I resolve data synchronization issues in an HA cluster?
- How do I resolve a heartbeat disconnection in an HA cluster?
- How do I replace a NAS in an HA cluster?
- How do I replace a hardware component in an HA cluster?
- How do I change the IP address of a node in an HA cluster?
- How do I schedule a shutdown in an HA cluster?
- How do I shut down both the active and passive nodes in an HA cluster?
Disks and Storage
- Can I change the location of my disks after setting up an HA cluster?
- How do I replace a hard drive with a larger capacity in an HA cluster?
- What should I do with HA disk slot inconsistencies after disk roaming?
- How do I swap spare disk roles after an automatic RAID rebuild in an HA cluster?
- Why can't I use the full capacity of a shared folder in an HA cluster?
- How do I expand a storage pool in an HA cluster?
- How do I repair a degraded storage pool in an HA cluster?
- How do I repair a degraded or crashed SSD cache in an HA cluster?
External Storage
- What JBOD enclosure models and quantities are supported in an HA cluster?
- Why do I encounter JBOD enclosure inconsistencies when pairing HA devices, even with identical configurations?
- How can I prevent HA pairing failure when using external storage devices?
- How do I update JBOD enclosure firmware in an HA cluster?
Software Updates
- How do I update firmware in an HA cluster?
- Why did I fail to update firmware on both HA cluster nodes?
- Can I downgrade QuTS hero from h5.3 (or later) to h5.2 (or earlier)?
- Can I update High Availability Manager if the two nodes have different firmware versions?
Cluster Removal
- Will the original passive node work after I remove an HA cluster?
- How do I reconfigure iSCSI targets on my NAS after removing it from an HA cluster?
Client Platforms and Other Apps
- Does Linux support SMB transparent failover in HA NAS clusters?
- Does macOS support SMB transparent failover in HA NAS clusters?
- Why is Boxafe not backing up data after a high availability (HA) switchover?
- Why am I unable to use CIP or heartbeat adapters as bridged interfaces in Container Station?
- Why does HA failover/switchover disrupt SMB file operations on a HybridMount mounted folder?
- Why do my iSCSI targets appear disconnected after an HA switchover?
- How does Security Center configure read-only shared folders in Standalone mode and in HA mode?
