Fri, 22 Aug 2008 16:31:45 +0100
> Yes, each guest has its own hostname/domain. On their arrival the
> device/router can distribute them to their servers respectively based
> on domain NOT on IP
>
>
>> For exemple Apache using mod_proxy.. Create a virtual host for each
>> website, and reverse proxy the requests to the internal vservers
>> (using
>> their private IP).
>>
>
> How about other servers, not webserver?
>
This sort of setup only works on HTTP and a very small number of other
services.
You need to go read a book on TCP. Basically DNS resolves www.abc.com
to an IP address, the host then makes a connection to the relevant port
at that IP, passes some data and that's the end of it.
With HTTP it coincidently happens that part of the data transmitted is
the name of the website you actually wanted to reach, eg www.abc.com -
this means that you can actually point lots of connections at a single
IP, BUT still distinguish the original desired site. With most other
protocols all you have is the fact that they connected to you, so it's
not easy to do virtual servers that way
The point of NAT though is that you can have port 53 on 1.2.3.4 mapped
back to your DNS server, port 80 on 1.2.3.4 mapped to a completely
different server doing apache, port 25 mapped to yet another server
doing mail, etc, etc. So one IP can be used for multiple machines as
long as the service is different
Good luck
Ed W
Yes, each guest has its own hostname/domain. On their arrival the
device/router can distribute them to their servers respectively based
on domain NOT on IP
For exemple Apache using mod_proxy.. Create a virtual host for each
website, and reverse proxy the requests to the internal vservers
(using
their private IP).
How about other servers, not webserver?
This sort of setup only works on HTTP and a very small number of other
services.
You need to go read a book on TCP. Basically DNS resolves
www.abc.com
to an IP address, the host then makes a connection to the relevant port
at that IP, passes some data and that's the end of it.
With HTTP it coincidently happens that part of the data transmitted is
the name of the website you actually wanted to reach, eg
www.abc.com -
this means that you can actually point lots of connections at a single
IP, BUT still distinguish the original desired site. With most other
protocols all you have is the fact that they connected to you, so it's
not easy to do virtual servers that way
The point of NAT though is that you can have port 53 on 1.2.3.4 mapped
back to your DNS server, port 80 on 1.2.3.4 mapped to a completely
different server doing apache, port 25 mapped to yet another server
doing mail, etc, etc. So one IP can be used for multiple machines as
long as the service is different
Good luck
Ed W