When I first heard that Citrix was releasing their flagship bare-metal hypervisor, XenServer for free, I was ecstatic. This is quite obviously a gauntlet being slapped down on VMware’s table, with VMware’s ESXi being released for free just 6 months ago. As a side note, Citrix’s timing was impeccable, as they released the news the day before one of VMware’s biggest user-community conferences,VMwareWorld Europe 2009 .
So, XenServer or ESXi? Check out this table: (disclaimer, from the Citrix site)
|Features included at no cost||Citrix XenServer||VMware ESXi|
|Max virtual CPUs||8||4|
|Windows® and Linux guests|
|Unlimited servers, VMs, memory|
|P2V & V2V conversion|
|Shared SAN and NAS storage|
|Centralized multi-server management|
|Resilient distributed management architecture|
|Shared VM template library|
|Centralized configuration management|
|Virtual infrastructure patch management|
|Intelligent initial VM placement|
|Intelligent server maintenance mode|
|Fine-grained CPU resource controls|
|Hot-swappable disks and NICs|
I was really hoping to be able to try out XenServer, but my home test box doesn’t have the needed requirements (64bit proc, etc), and I currently don’t have access to any test machines at the organization I serve with. The only machine that comes close to the requirements is my personal laptop that is already dual-booting Ubuntu and Vista. So I thought I would try to install it on external usb media.
The best exertnal media I could come up with was a old ide 2.5″,40GB hard drive I had pulled out of a laptop recently. So, using a ide-2-usb adapter, I booted up the XenServer installer, making sure to select the external hard drive to install to.
After the reboot, expecting for the external drive to boot, I see XenServer starting to load, then a kernel panic, and a reboot. Well, after watching this process for a minute, I was able to discover that the kernel was panicing because of something to to do with booting from a usb device.
After doing a bit of googleing, I was able to find this guide, that helped me enable usb support in intird to allow usb booting. (I did have to tweak the instructions a bit, since I was installing 5, and not 4.1)
After working this black magic, I got XenServer to boot on my laptop. After installing the Xen client on another laptop, I was able to admin the server.
I really like it!
The biggest feature for me, and why I will be using it over ESXi, is that Citrix made the VM manager, XenCenter, free, instead of charging for it, like Vmware is doing with VMware Infrastructure 3.
I’m sure I will be blogging more about it, but I thought I would just post about the educational install! :)
Edit (05/09): As requested in a comment: To tweak the enabling usb support in initrd for 5.0 U3, I just had to use the updated filename for the primary initrd image file, instead of the quoted primary initrd image file, since it was for 4.1.