Applicable Products
- QuTS hero h5.3.0 or later
- High Availability Manager
Background
High availability (HA) allows two QNAP NAS devices to form an active-passive setup for uninterrupted service. The active node provides services while the passive node continuously syncs data from the active node, ready to take over any time. This transition is called a failover if triggered by a failure, and a switchover if triggered by non-failure events.
When synchronizing data during HA cluster creation, the system needs to replicate a large amount of data from one node to the other. For failovers or switchovers, the system needs to ensure seamless continuation of applications and services. The time required for these operations can vary significantly depending on hardware specifications, storage configuration, and network conditions.
Details
The actual time required for initial synchronization and for a failover or switchover depends on the following factors:
- Data volume: Larger amounts of data increases synchronization time.
- Storage performance: HDDs are slower than SSDs. RAID configuration also affects performance.
- Network conditions: The heartbeat connection speed affects how fast data is transferred (we recommend using ports and a direct cable connection of 10 GbE or faster).
- System load: Ongoing services and background tasks may consume resources and slow down the process time.
- Applications and services: It takes time to shut down and restart each application and service, especially in an environment with iSCSI LUNs.
Typical Time Ranges (Reference Only)
| Process | Typical Time Range |
|---|
| Initial synchronization | Tens of minutes to several hours |
| Failover/switchover | Around 30 seconds to several minutes |
| Failover/switchover with multiple iSCSI LUNs | Several minutes to tens of minutes
The more iSCSI LUNs there are, the longer it takes. |
Note
The actual time required depends on your environment and system configuration. We recommend performing switchover tests during non-production hours to evaluate performance in your specific setup.
Further Reading
How can I reduce initial synchronization time for my HA cluster?
适用产品
- QuTS hero h5.3.0 or later
- High Availability Manager
背景
高可用性 (HA) 允许两个 QNAP NAS 设备形成主动-被动设置，以确保服务不中断。主动节点提供服务，而被动节点持续从主动节点同步数据，随时准备接管。若因故障触发，此转换称为故障转移；若因非故障事件触发，则称为切换。
在创建 HA 群集 时同步数据时，系统需要将大量数据从一个节点复制到另一个节点。对于故障转移或切换，系统需要确保应用程序和服务的无缝继续。这些操作所需的时间可能会因硬件规格、存储配置和网络条件而显著变化。
详情
初始同步以及故障转移或切换所需的实际时间取决于以下因素：
- 数据量：数据量越大，同步时间越长。
- 存储 性能：硬盘比固态硬盘慢。RAID 配置也会影响性能。
- 网络条件：心跳连接速度影响数据传输速度（我们建议使用端口和 10 GbE 或更快的直接电缆连接）。
- 系统负载：正在进行的服务和后台任务可能会消耗资源并减慢处理时间。
- 应用程序和服务：关闭和重启每个应用程序和服务需要时间，尤其是在有 iSCSI LUN 的环境中。
典型时间范围（仅供参考）
| 过程 | 典型时间范围 |
|---|
| 初始同步 | 几十分钟到几个小时 |
| 故障转移/切换 | 大约 30 秒到几分钟 |
| 故障转移/切换与多个 iSCSI LUN | 几分钟到几十分钟
iSCSI LUN 越多，所需时间越长。 |
注意
实际所需时间取决于您的环境和系统配置。我们建议在非生产时间进行切换测试，以评估您特定设置中的性能。
进一步阅读
如何减少我的 HA 群集 的初始同步时间？
