Recently I decided to upgrade a web and mail server, from Ubuntu Jaunty to Karmic.
After carefully backing up the system and making sure I could run a secondary system in its place if things went wrong, I started the upgrade process using Ubuntu’s update-manager application. It offered me the upgrade, I clicked a few OK buttons, and the upgrade got started. It took about an hour for the upgrade packages to download, and another 40 minutes or so for them to install and configure before the system was ready for reboot.
As an experiment, I left the server up and live for the whole process, to see what would happen.
The server retained all its functionality for the entire time the updates were downloading and being prepared. When the installation and configure phase started, the mail agents became unavailable, but Apache stayed up and served web pages the whole time, including SSL connections. It was slow at times, because of the processor load from the upgrade, but it stayed up.
When the upgrade process completed, a reboot brought the system back up cleanly with no problems.
Final results: Total time about 1 hour 45 minutes. Mail was down for about 45 minutes of that time; web was down for less than five.
Can a Windows server do that? A version upgrade, in place, without taking down the server, and with minimal offline time? I don’t think so. I never really appreciated the convenience of being able to continue to use a Linux system during an upgrade until I needed to upgrade a working server. It’s nice.
[...] Upgrading an Ubuntu server on the fly Can a Windows server do that? A version upgrade, in place, without taking down the server, and with minimal offline time? I don’t think so. I never really appreciated the convenience of being able to continue to use a Linux system during an upgrade until I needed to upgrade a working server. It’s nice. [...]