JDPFu.com 2024

Next, I wanted to verify a migration of Xen VMs from the current C2D E8400 server. I began with our disaster recovery instructions in hand loading Ubuntu Server 8.04.×. I decided to use XFS instead of JFS based on recent articles proving that XFS was a little faster. I setup partitions like this

• / – 20G
• swap – 6G
• /export – 110G
• /backup – remaining
  but used XFS. Well, I didn’t notice it at the time, but the selection of XFS forces LiLo to be used as a boot loader. That, by itself isn’t immediately bad. The OS for Dom0 was loaded and I started patching it to current levels, 8.04.4. That went fine until apt-get install ubuntu-xen-server caused LiLo boot issues. Based on the error, I needed to find a disk drive with 1024 or less cylinders. Screw that.

Grub / JFS

My answer was to reload the OS, chosing JFS this time. That automatically enabled Grub as a boot loader. Life was good and I got to practice bare-metal DR twice. Got the system all patched and loaded the Xen hypervisor. Life was looking good Winthorpe.

VM Migration

I selected a little used VM from the other Xen server and shut it down. Used rsync to mirror the IMG file with swap to the new machine. Placed everything Xen related where it needed to be and did a
xm create -c /etc/xen/small.cfg
This brought up the new VM without any issues. I ssh’ed in from a trusted client, wasn’t prompted for a password, feeling good Mortimer. For a few more minutes, I looked around inside the VM and tested the services from outside it. There wasn’t any difference – the DR plan had worked flawlessly except, well, the 2 servers were 2 feet apart.

At least all the design decisions made over the last year have been proven out. Picking up a DR VM package and moving it to different hardware (these 2 servers are very different after all) allowed me to bring up the VM exactly as it was on the other server. Further, the VPN front end didn’t care that it was physically running on a different machine. As long as the IP/DNS address didn’t change, it worked.

What’s left? Well, I’d like to

1. migrate everything off an ESXi 4 server onto this new box
2. migrate from Xen to KVM since Ubuntu 10.04 will include Eucalyptus private cloud support

The server hardware isn’t ready for production use. I’m a little uncomfortable with just 1 disk drive inside and it is a 4 yr old IDE at that.

I can’t really do much more at this point. so this is the end of the New Server Build series. I hope you enjoyed reading it.