Here it is the procedure.
The procedure is a development procedure and does not work in production as soon as the domain name is different of localhost.
The procedure consist to add a parameter to simulate any slave site defined in JMS.
The method consists to add _host_=xxxx parameter in the URL where xxx is the slave site domain name to simulate.
Suppose you have defined in JMS a
www.slave1.com
If you want to login in the administration of this website
localhost/master/administrator/?_host_=http://www.slave1.com
There are some constraints.
You can not have ANY website defined in JMS with
localhost or the _host_ parameter will be ignored.
The _host_ parameter will result in saving the current selected slave site into the session.
This means that when you log off, or when session expire, you are automatically returned to the master website.
This method is usefull to have the same JMS definition than the one used in production.
I hope this will help you and I remember you that this feature only works with localhost and is unavailable when you working with real domain name.
This feature also assume that you don't use the Symbolic Link and specific folders for the slave sites.
This is a feature used for developement and there are limitations.