This is currently a place for me to keep notes on my experimentation with Xen
Creating a Centos virtual machine from scratch
Redhat/Centos has a very very nice way of creating DomU. This is the most useful reference:
Only 1 partition necessary – mounted on root. After install you can tar up the entire root and use it as a template for subsequent DomUs.
What I wanted to achieve
- Most existing setups seem to be overly complex!
- The Shorewall guy looks like he really knows his stuff but it is way too complicated for my liking: http://www.shorewall.net/Xen.html
- Minimal exposure of DomU to the Internet.
- Currently solutions for commercial ‘dedicated servers’ in remote datacenters are not very well documented. These servers typically come with /29 IP assignment (8 IPs – 5 usable IPs). Flexibilty means a DomU does not necessarily have to be assigned a dedicated IP address but can be configured to listen on specific IP addresses and ports.
“Virtual Network” solution – A dummy network interface is created on Dom0, and this interface becomes the one bridged to all DomUs instead of eth0. Dom0 is then configured to act as a gateway/router/firewall to the DomUs.
Interestingly enough, this method seems to be documented in the RHEL virtualization manual under “Laptop Configurations”:
This is a nice solution as it doesn’t require much deviation from the default Xen configuration except to tell it to bridge the dummy interface instead on eth0. NAT rules will need to be setup and these act as a firewall as well.
maybe not? Perhaps a better solution is for each DomU to have its own private virtual network with the Dom0?