Subject: Re: [vserver] Newbei's questions
From: Martin <inkubus@interalpha.co.uk>
Date: Sun, 20 Apr 2008 22:03:37 +0100

On Sun, 2008-04-20 at 23:50 +0800, Stephen Liu wrote:
> --- Martin <inkubus@interalpha.co.uk> wrote:
> 
> > The
> > only other solution I can think of is that some of the commercial
> > vendors may be able to sell you (at great cost) switching gear that
> > can
> > route on the basis of packet content.  This would likely be extreemly
> > expensive and I suspect it wouldn't work very well for your needs.
> 
> 
> Can vyatta help?
> 
> http://www.vyatta.com/
> 
> 
> I learned this project for sometime.  Unfortunately I don't have time
> testing it.

No idea, never used one.

> > If you want to run two or more, independant, web servers both on port
> > 80, you will need more than one IP.
> 
> 
> Actually what I want to achieve is;
> 
> Running mail server on Host OS
> Running web server on Guest OS
A more normal set up would be to run all services on guests and keep the
host for admin.  The reason is that if the host is compromised, so are
all guests (but not vica versa), so it makes sense to minimise the
number of services / amount of use of the host.

> I have SquirrelMail, the webmail, running on the mail server.  It needs
> port 80.  However Apache also needs port 80.  I can't figure out how to
> let them sharing port 80.
As I have said before, you can't have two programs sharing the same port
on the same IP.

>   This is my problem.  If w/o a solution then
> I must run both web and mail servers on the Host.
With vserver you can share filespace between guests and between guest
and host, one solution would be to share the mail spool / homespace
between the web and mail servers.

Another option would be to run the webserver for the webmail on a
different port.  Personally, I wouldn't use a webmail service that
didn't run over SSL, so why not run two web servers, one on the same
(logical) server as the mail server running webmail on port 443 w/ SSL
and one in a separate (logical) server running the rest of the web apps
on port 80.  If you wanted to make things more transparent you could add
the appropriate vhost record to the web server on port 80 so that it
redirects http://webmail.example.com to https://webmail.example.com 

Cheers,
 - Martin