通常，您可以从 HTTP 头部中提取此信息，但是 HTTP 头部不可使用，因为视图构建在服务器上。

Normally, you can pull this information from the HTTP header, but the HTTP header isn't available because the view is built on the server.

youdao

如果一个特殊的应用程序服务器实例被停止或因其它原因不可使用，则忽略该实例(不要尝试选择它)，直到验证了它可以重新提供服务为止。

If a particular application server instance is stopped or otherwise unavailable, that instance is skipped (no attempt is made to select it) until it can be verified as being back in service.

youdao