Overview
This page displays basic information regarding the high-available cluster and member servers. In addition, this page provides tools to create, remove, or perform maintenance on high-availability clusters and member servers.
High Availability Cluster Status
This field displays the overall status of your high-availability cluster, alerting you to any errors. The following is a list of possible conditions displayed in this field:
- Standalone: The servers are not combined into a high-availability cluster.
- Healthy: The overall condition of your high-availability cluster is good. Data replication from the active server to the passive server is functioning normally.
- Preparing: The servers have been successfully combined into a high-availability cluster, but initial data replication has not yet finished. Switchover cannot be performed at this time. For more details, please refer to Switchover.
- Warning: The high-availability cluster exists, but certain services or data replication might not be functioning normally. This warning appears under the following conditions:
- Error occurred on the active server: This is a temporary situation. In this instance, the high-availability cluster will switchover services to the passive server. Errors might occur on the active server as a result of the following:
- Error on a monitored service.
- RAID Group on the active server is degraded or crashed. Please check the Storage Status page.
- Disk error on active server. Please check active server tab on the Disk Status page.
- Error occurred on the passive server: Please check the Storage Status or Disk Status page to determine the reason of malfunction. In this case, switchover will be unavailable. Errors might occur on the passive server as a result of the following:
- RAID Group on the passive server is crashed or degraded. Please check the Storage Status page.
- Passive server disk error. Please check the passive server tab on the Disk Status page.
- Failed to detect passive server: This error might occur because the passive server is offline or the active and passive servers cannot connect through the Heartbeat connection. In this case, switchover will be unavailable.
- Data cannot be replicated to passive server: This error might occur due to storage volume or disk failure. In this case, switchover will be unavailable. Please check the Storage Status page.
- Passive server is not selected: If the passive server is unbound from the high-availability cluster, this status will be displayed. In this case, switchover will be unavailable. If you wish to rebind the passive server, click the Maintain drop-down menu and click Bind. When you rebind the passive server, a full data replication will be required.
- Danger: Both the active and passive servers are malfunctioning. The high-availability cluster is unable to function normally. Please check the status of all RAID Groups, volumes, and iSCSI LUNs.
High Availability Cluster Information
This field is located below the high-availability cluster status and displays basic information regarding the cluster. If a high-availability cluster does not exist, this field will only provide an explanation of the function of high-availability clusters.
This field includes the following information:
- Cluster Server Name: The server name used by the high-availability cluster.
- Cluster IP Address: The IP address used by the high-availability cluster. Regardless of which server is running services, users can connect to the high-availability cluster using this IP address.
- Cluster Uptime: Time elapsed since the high-availability cluster was created.
High Availability Cluster Operation Buttons
The following two buttons are located beneath the high-availability cluster information:
- Switchover: Clicking this button initiates a switchover of the active server to the passive server. During this process, the active server stops providing services and becomes a passive server. Then, the passive server changes to the active server and begins providing all services of the high-availability cluster. This option is unavailable when the passive server is malfunctioning or not selected.
- Create HA Cluster: When no high-availability cluster exists, you can click this button to combine two servers and create a high-availability cluster. For more information about creating a high-availability cluster, please refer to Synology High Availability Wizard.
- Manage HA Cluster: This button is available only when a high-availability cluster already exists. Click this button if you wish to remove the high-availability cluster or shut down the active and passive servers.
Note: Once a high-availability cluster is removed, data replication will be required when you wish to create a new one.
Server and Data Replication Status
This section contains images that indicate the status of the active and passive servers, as well as the flow of data replication between the servers.
The images of the active and passive servers indicate the following possible conditions:
- Standalone: Indicated by blue lights on one server and a dotted outline representing the other server.
- Healthy: Indicated by green lights on both servers.
- Warning: Indicated by yellow lights on the problematic server.
- Danger: Indicated by red lights on the problematic server.
- Failed to detect passive server: Indicated by a translucent image of the offline server.
- Passive server is not selected: Indicated by a dotted outline representing the passive server.
The image of data replication indicates the following possible conditions:
- Data replication functioning normally: Indicated by data flowing from the active server towards the passive server.
- No data replication: Indicated by the absence of the data flow image.
Server Information
This section is located beneath the server images. Information regarding the active and passive servers is displayed in this section. If no passive server has been selected, this section will read N/A.
- Server Name: Synology server name.
- Model Name: Synology server model.
- Serial Number: Serial number of the Synology server.
- Fan Status: Status of a server’s cooling fans. If a fan malfunctions, a warning will appear. In this case, please contact your local distributor for assistance.
- Temperature: Temperature of the Synology server.
- Power Status: Indicates whether or not the power supplies on a server are all functioning normally. If the server model is equipped with redundant power supplies, a warning will appear if one of them is malfunctioning.
Maintain Buttons
The Maintain drop-down menu is located beneath the server information section. This drop-down menu contains options for conducting maintenance on the passive server. When no high-availability cluster exists, this menu will be grayed out.
- Shut down: Select this option to shut down the passive server. This action does not remove the passive server from the high-availability cluster. We recommend using this option when conducting maintenance on the passive service is necessary. This button is grayed out when the passive server is already off or when the Passive server is not selected.
- Bind/Unbind: Clicking Unbind removes the passive server from the high-availability cluster. Clicking Bind adds the passive server back to the high-availability cluster. When a server is added to the high-availability cluster again after unbinding, a full data replication will be necessary. Therefore, we recommend using this option only when you wish to replace the existing passive server with a new one.
Note: Shutting down or unbinding the passive server will cause the high-availability cluster to be without a passive server and unable to switchover from the active server to the passive server.