Subject: Re: [vserver] Virtual Host-Only Networking (tap?)
From: Gordan Bobic <gordan@bobich.net>
Date: Sat, 11 Sep 2010 23:14:45 +0100

On 09/11/2010 10:36 PM, Adrian Reyer wrote:
> On Sat, Sep 11, 2010 at 11:19:07AM +0100, Gordan Bobic wrote:

[snip]

> Be aware
> I don't use VServers for security reasons, but to be able to
> administrate e.g. the webserver seperate from the database server,
> despite both are small enough to run on the same host. I don't run
> e.g. potentially hostile webservers on my hosts. So any security flaws
> that relate to inner-VServer/host are no real concern to me and I
> actually only spent minor thoughts on it.

Interestingly, in my case, the main reason why I am separating things 
into vservers rather than run them on bare metal is precisely because I 
want more isolation for security reasons. If somebody finds a 0-day 
exploit in a CMS and pwns Apache and gains some level of access to the 
host, I don't want that to be on the same host containing, say, a mail 
server.

That's mainly why I was asking about guests' access to services running 
on loopback on the host. But then again, I see no reason why the 
loopback interface on the host couldn't be suitably firewalled to 
prevent the obvious problems. I was just wondering if there is something 
obscure yet dangerous about this sort of a setup in terms of security.

Gordan