I figured I would share my experience running trixbox on xen (which is a virtualization technology for those who may not know - http://www.xensource.com/xen/). I originally had a little celeron 350 running asterisk at home quite well. I upgraded my main workstation and decided that the older motherboard/CPU could be used as an interesting little project to consolidate the [really] old hardware I had running various servers - file, web, asterisk, etc. The hardware: AMD 1800+ (1500 Mhz), 768 MB RAM, couple of hard drives. I performed a very basic installation of Ubuntu breezy and installed and configured the xen binary installation. I knew I wanted some flexibility with the disk layout, so I created a metadevice and used lvm to slice it. More information on the xen installation is at: http://phorkar.blog-city.com/xen_install.htm for those interested in the gory details.
Once I had xen and the first virtual machine running it was time to install trixbox. I wanted to use the default cd installation instead of installing centos by hand and then adding trixbox so I used vmware player to perform an installation of trixbox from a cd-image. Once the installation was working and I had tested it a little bit, including connecting some soft phones, I tarred up the file system within vmware (in single user mode - i.e. asterisk , mysql and friends downed), copied it to a new partition on the xen server, untarred it and tweaked a couple of things (new IP address, etc), defined a new xen virtual machine definition file and booted it. There were a few hiccups but they were fairly easy to resolve and next thing I knew, I was running asterisk on xen. I use a Sipura spa-3000 for pstn integration so I didn't have to worry about integrating a PCI card into the mix. This does mean that I am without conference capabilities (I haven't managed to get ztdummy compiled and running happily but I haven't tried too hard), but for my installation, that's not a big deal. I have now been running exclusively on the xen install for about six months and have been very happy with it. I met my goal of consolidating some older equipment into a single server and have had zero problems with trixbox running this way. The hardware is running three virtual machines: 1) trixbox 2) an external web server with php, mysql and a few goodies and 3) an internal web server. The hardware apears that it could handle more virtual machines but I have allocated all the RAM - I am sure if I added more memory that I could boot at least two other virtual machines. I have successfully upgraded to trixbox 1.1.1 using the trixbox update script. My telephone IP network is (mostly) on a dedicated subnet and the xen host has multiple network cards and is routing between the two subnets - this wasn't so much by design as by necessity as I didn't have enough free ports on my switch at the time but I did have a dual port Intel NIC kicking around. So, if you've been thinking about using xen to run an asterisk installation take this as my positive experience in so doing. Of course, in most commercial installations this may not be the best option for a variety of valid reasons, but for a home installation its great. One of my next projects is to see if I can integrate some high availability into my installation, that is, have two computers each running xen be able to keep the filesystems in sync and take over a downed virtual machine in the case of a failure (or for maintenance): since my asterisk installation just needs an IP address, I should be able to bounce it around the network without too much trouble. -- sacha
