SQL Server-AlwaysOn real-day

Personal experience of a project, the boss suddenly proposed that the database of the debt to implement a diversion, a database one responsible for reading, and the other responsible for writing, background is required to synchronize the state of two databases. Find a lot of information, found that the new version of AlwaysOn can achieve this feature.

Having studied the extensive data of AlwaysOn, he found that his functions were increased, not only by the original share disk architecture, but also by adding greater flexibility, reportedly replacing log shipping and mirror database. Not to help Microsoft brag, really improve a lot, but still a library is read-only, one to be able to read and write.

The implementation of the specific steps, and in the implementation of the problems encountered and solutions:

An implementation of the architecture

We used three servers, two of which were SQL Server and the other was a file server (to vote). The schema is as follows:

Microsoft has written a white paper, he introduced the construction is four machines, one of the different sites, our company is not so rich, we just adopted 2 machine architecture.

The specific Microsoft documentation can be referenced in the document list after me.

Two preparation steps

Consider what kind of voting structure to use. Before that, Microsoft used the architecture is share disk's high-redundancy construction, because to use shared storage, many conditions difficult to implement, only to adopt the current methods of the machine, the new addition has three kinds, a total of four kinds, such as the following, is Microsoft's words, not many explanations, interested can follow my link, research.

But the general rule is that the total number of servers is best to be odd.

We work with 3 servers (one for file servers)

Three detailed steps are as follows

SQL Server-AlwaysOn real-day