Zendredirect jump is going crazy, for help

Zendredirect jump is going crazy. For Help $ this-> _ redirect ("localhost/a/index ");
$ This-> _ redirect ("/index ");

Do I have to carry a domain name when redirecting from redirect ???
The first method for local testing is easy to use, but it is not easy to use when it is released to the official environment. it is a white page. please help me !!!

Reply to discussion (solution)

2nd servers should be used, because localhost is local

2nd servers should be used, because localhost is local

Switch to the server with the second is also a white page

The second is the white page, indicating that the path is incorrect. open the error and debug it.
Both methods can be used.
Configure the domain name of the current server if the first type is used. configure localhost/server to configure www.xxx.com/
Then you can directly read this and splice it. Finally, as long as the local and server configuration files are different.
Another method is to read $ _ SERVER ['http _ host'] but not frequently used.

The web server corresponds to the correct directory.

It may be because I put it in sae and changed it to a domain name. no matter what, thank you for your reply.