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I’ve been using virtualized systems for years now and finally began using Xen. Xen is similar to a bare-metal hypervisor like VMWare ESX but instead of using a proprietary host OS, Xen uses Linux. Most of the common Linux distros like Debian/Ubuntu, RHEL/Fedore/CentOS, etc provide support for Xen out of the box. I’m used to using Linux and have used it for years, so it just made sense.

Previously I had used VMWare Workstation for creating test servers, etc., but that required a full host operating system. For a while, I had used Windows, then I was using Linux, but it was still clunky. I had to manually start machines after reboot and if I upgraded the kernel on the host, I had to re-run some perl script to configure VMWare. After a while, I realized it was time to let go and do things the smart way, the Xen way. However, I do still use Parallels Desktop on my Mac just to have something available when I travel.

I have a custom server in my basement that I built a few years back and have modified over time. It has a 2TB RAID 5 array that I use for my network storage. It also has a dual-core AMD processor that I might swap out for a quad-core Phenom early next year. Just before rebuilding it as a Xen box, I upgraded the RAM to the maximum 8GB. Oh, and I added a 640GB drive to store my Xen machines.

I got the Xen Dom0 built the other week and have it running just enough to basically boot and allow me SSH access. This was really just a matter of doing a base install plus the Xen kernel and booting to the Xen kernel post-install. I kept the services to a minimum for security purposes and will run what’s needed off one of the DomU machines. Before I rebuilt this box with Xen, the host OS also doubled as the file and print server. This will be moved over to the first Xen DomU I create.

CentOS 5.2 comes with Xen 3.0 and unfortunately, none of the default repos have Xen built other than 3.0. Xen 3.0 is fairly outdated and I was looking to update to a more recent version to take advantage of the new features. The only options for updating were to upgrade/install from source or to use the wonderful Gitco repo that has a few Xen versions built for EL5 based operating systems.

I’m now the proud owner of a Xen box! I’ve learned quite a bit so far and have gotten my first DomU created. I’ll detail that more in a later post. I’m also looking at setting up Puppet to deploy and manage my machines. That’ll probably be the second DomU that I create.

I’ve finally made the transition to my new routers at home. I don’t have anything wireless N yet, but I bought two new Linksys WRT600N’s just for the Gigabit switches built in. I wanted the speed for when I transfer large files, and since all my laptops have Gigabit NICs I can just plug in for a few minutes if I need to transfer something. The main reason for this is that my office is upstairs and my server is located in the basement where it’s nice and cool.

I’ve been a DD-WRT fan for many years, and had been a hardcore user of the Linksys WRT54G (and later WRT54GL after Linksys cut the memory in the WRT54G). I’ve had my eyes on the new N routers, especially one with a Gigabit switch and finally pulled the trigger the other month. I’m running a v24 pre SP2 build (svn 10431 to be precise) and it seems to be working fine. I have my main router set up to handle DHCP and the second router forwards request to the main one. Wireless is set up on both so no matter where I am in the house I have coverage.

I also set up a second BSSID, or virtual wireless access point to allow visitors internet access. The SSID doesn’t broadcast, but it’s open for up to 5 users if you know the name. It’s cut off from the rest of my network for security. I just got tired of dealing with people visiting and having them connect directly to my network and having to give them credentials to connect. Not cool. This was a feature of DD-WRT v24, if your router supported it. Cliff Pennock has an awesome tutorial on how to set this up.

I’m quite content now that I have everything working as expected and my network is blazing fast. Now I can get back to working on my Xen server and building virtual machines!