The Citrix NetScaler can be placed in front of a webserver farm that is running Apache. The same re-write rules that run on Apache, can be implemented on the Citrix NetScaler.
Some sites with thousands of users usually use a structured homedir layout, i.e. each homedir is in a subdirectory which begins for instance with the first character of the username. So, /~foo/anypath is /home/f/foo/.www/anypath while /~bar/anypath is /home/b/bar/.www/anypath.Following rules could be used to implement this.
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