I honestly believe that VMware ESXi 5.1 is the best hypervisor out there at the moment. When using it in a production environment, I never experienced slowness or downtime. But it did have it’s limitations, and not having thousands of dollars to spend on power, servers, and software such as vSphere, or vMotion, I had to look for another alternative. The major options were Citrix’s XenServer, or Microsoft’s Hyper-V. I picked Citrix over Microsoft, for obvious reasons (downtime and updates). But after about four months in production, I am starting to wonder if it was worth it to move to Citrix. I had many instances where VM’s locked up or were slow. While some issues have been resolved with updates, it just doesn’t have as much power as my VMware server did. While I am disappointed by that, there are many features that makes it worth using. I wanted to test live migration, and virtual desktops. Citrix was the only free option out there, and so I used it.
XenServer – Setup and Configuration
My deployment included two IBM x3650’s 7979 servers running XenServer 6.1. Now XenServer 6 and above allowed servers to be stored locally and used for live migration, but it is not ideal. When I was running VMware, I had 3TB of storage space local, because I had only one server, but when I implemented another host, I could no longer use local storage, so I invested in a storage server. I picked up a Dell poweredge 1950 and configured it with 1TB of storage and installed FreeNAS to run the iSCSI volume. I even had to upgrade my switch to gigabit, so I found a nice used Cisco 2970. Now when I configured the Xen Servers, they process and deal with data on the server level, but store it on the storage server using the LAN as a medium. Once XenServer was installed on the IBM servers, the process of setting them up and configuring them in a pool took place. I had a few issues with configuring the BIO’s and matching the CPU types, but once that was all set and done, the pool configuration went rather smoothly. I could now migrate servers from one to another without shutting them down.
I had a server set up, and it worked, but had no servers… Well they were backed up VMware ones. Turns out, you can import them, and they will auto convert to Xen images. This made the import rather easy, and automatic. I later found out that some machines did not convert easily, and had to be reformatted to operate properly.
XenServer – Production Environment
After four months of using XenServer, I can say that it has it’s ups and downs. It doesn’t seem like it has the power that my other hypervisor had, and locks up and gets VMs stuck in weird loops. But having live migration, and quick boot times, can be nice. I am hoping that XenServer only improves and I get to see more benefits.
This post only detailed on XenServer, not XenDesktop or other servers. Later posts will involve information about these programs.