Comments on OpenVZ On Debian Etch For Webservers
OpenVZ On Debian Etch For Webservers Virtualization is nice! A good practice for servers, since it makes things more secure, scalable, replacable, and replicable. All this at the cost of little added complexity. This guide is written during an install of a Supermicro machine with 2 dual-core opterons (64-bit), 2 identical disks (for RAID) and a load of memory. Why OpenVZ and not XEN or the recent KVM kernel module? Well, XEN is not very stable for 64-bit architectures (yet), and it comes with quite a bit of overhead (every VM runs its own kernel) due to its complexity. KVM is very simple but restricts you to run a kernel as one process, so the VM cannot benefit from multi core systems.
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Let me warn you that your configuration is wrong. You should always check the changes you made to a VE configuration using the vzcfgvalidate tool. In your case, it gives (at least) the following:
Error: othersockbuf.lim-othersockbuf.bar should be > 652800 (currently, 0)
Warning: tcprcvbuf.lim-tcprcvbuf.bar should be > 204800 (currently, 0)
The problem is quite severe: since you set the barrier and the limit for othersockbuf to the same value, there is no "safety gap" between bar and lim, thus the system will act severe if there will be othersockbuf shortage. Same problem with tcprcvbuf.
For more info about these specific parameters, see http://wiki.openvz.org/UBC_secondary_parameters
For info of how to configure your UBC (and other resource management) settings, see http://wiki.openvz.org/Resource_shortage
Overall UBC info is at http://wiki.openvz.org/UBC.
Finally, it makes no sense to publish a config with IP_ADDRESS and NAMESERVER variables.
I want to warn you, that there is no any prepared image in /var/lib/vz/template/cache in Debian Etch by default, you should get it manually from http://openvz.org/download/template/cache
In this how-to it is not mentioned, that virtual machines will not have access to internet. To allow VM acces internet, you must enable NAT on hosting server:
iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to external_ip