[courier-users] Re: webmail non-relative urls

[Sam V. <mr...@co...>]

Graham Leggett writes: 

> Sam Varshavchik wrote: 
> 
>> "Reverse proxy" is a meaningless buzzword.
> 
> Explain? 
> 
> A reverse proxy is a webserver that serves pages from another webserver,
> instead of the typical files, CGI, etc. They are hugely useful for URL
> management and centralised logging, especially where you run a website
> using multiple architectures behind it.

That's not a proxy - that's a hack.  All of the above tasks can be handled 
in a completely transparent manner by many kinds of load-balancing software. 


>> The URL is not hardcoded.  You can rename sqwebmail as my-webmail-server,
>> and http://hostname/cgi-bin/my-webmail-server will work just as well.
>       ^^^^^^^^^^^^^^^^^^^^^^^ 
> 
> ...but because the highlighted stuff is hardcoded within the pages, this
> will cause the reverse proxy to be bypassed, telling the browser instead

That's what happens if the so-called "proxy" modifies the real URL. 

>> If the URL received by the web server is not the same URL that was issued by
>> the client, the proxy is broken, and needs to be fixed.  That's the real
>> problem.
> 
> You are talking about a forward or transparent proxy. A reverse proxy is

That's what a proxy is, by definition: transparent. 

> something different.

Yes -- it's not a proxy, but something else. 


-- 
Sam