Azure SQL数据库自动故障转移组

本文介绍了Azure SQL数据库自动故障转移组的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

参考:使用自动故障转移组以实现多个数据库的透明且协调的故障转移

根据以上参考资料:

自动故障转移策略

默认情况下，故障转移组配置有自动故障转移策略. SQL数据库服务触发故障转移 检测到故障并且宽限期已过期 .系统必须验证内置高 SQL Server服务的可用性基础结构的影响范围.如果要从应用程序控制故障转移工作流程，则可以关闭自动故障转移.

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问题:

这意味着与之间的延迟无关这两个节点，如果打开了自动故障转移功能，数据库将在一小时后进行故障转移吗?

OR

如果延迟时间超过一个小时，则会在 GracePeriodWithDataLossHours 通过?

解决方案

GracePeriodWithDataLossHours 意味着此设置将控制Azure启动故障转移之前等待的时间，该灾难转移可导致灾难降临主要节点时丢失某些数据，而与节点之间的延迟无关.默认值为一小时，最长为24小时.

Ref:Use auto-failover groups to enable transparent and coordinated failover of multiple databases

From the above reference:

Automatic failover policy

By default, a failover group is configured with an automatic failover policy. The SQL Database service triggers failover after the failure is detected and the grace period has expired. The system must verify that the outage cannot be mitigated by the built-inhigh availability infrastructure of the SQL Database servicedue to the scale of the impact. If you want to control the failover workflow from the application, you can turn off automatic failover.

Currently default value for 'GracePeriodWithDataLossHours' is one hour.

Question:

Does that mean irrespective of latency between the two nodes, if auto failover is turned on database will failover after one hour?

OR

If latency is over an hour, failover will happen afterGracePeriodWithDataLossHours is passed?

解决方案

GracePeriodWithDataLossHours means that this setting will control how long it will wait before Azure initiates the failover that could result in loss of some data when disaster strikes the primary irrespective of latency between the nodes. Default is one hour and maximum is 24 hours.