> For the complete documentation index, see [llms.txt](https://docs.natsclub.cn/cn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.natsclub.cn/cn/yi-chan/stan/intro/ft/active-server.md).

# Active Server

There is a single Active server in the group. This server was the first to obtain the exclusive lock for storage. For the `FileStore` implementation, it means trying to get an advisory lock for a file located in the shared datastore. For the `SQLStore` implementation, a special table is used in which the owner of the lock updates a column. Other instances will steal the lock if the column is not updated for a certain amount of time.

If the elected server fails to grab this lock because it is already locked, it will go back to standby.

***Only the active server accesses the store and service all clients.***