The one problem with Xen is transparent high availability of your servers, sure you can snapshot an image but thats only of you shutdown the virtual machine. How excited was I when Remus announced that it has been applied to the official Xen repository, and is expected to be included with the next major release. Bookmark this page for a soon to be released how to install Xen with Remus support on CentOS 5.4!
What is Remus?
Remus provides transparent, comprehensive high availability to ordinary virtual machines running on the Xen virtual machine monitor. It does this by maintaining a completely up-to-date copy of a running VM on a backup server, which automatically activates if the primary server fails. Key features:
* The backup VM is an exact copy of the primary VM. When failure happens, it continues running on the backup host as if failure had never occurred.
* The backup is completely up-to-date. Even active TCP sessions are maintained without interruption.
* Protection is transparent. Existing guests can be protected without modifying them in any way.
For a full description and evaluation, see their NSDI paper.
Visit the project: http://dsg.cs.ubc.ca/remus/
We all know the importance of creating a local YUM repository on your LAN. Not only do you decrease the time it takes to download and install updates, you also decrease bandwidth usage.
This How To will show you a simple yet effective way of setting up your local Fedora YUM server and client.
TIP: Distribute your Fedora YUM configuration via your Puppet Master
Daxos: I see I was wrong to expect Sparta’s Linux commitment to at least match our own.
King Leonidas: Doesn’t it?
[points to Arcadian linux user behind Daxos]
King Leonidas: You there, what is your Distro?
Free Greek-Slackware user: I am a Slackware user… sir.
King Leonidas: [points to another linux user] And you, Arcadian, what is your Distro?
Free Greek-Debian user: Debian, sir.
King Leonidas: Debian.
[turns to a third linux user]
King Leonidas: You?
Free Greek-Ubuntu user: Ubuntu.
King Leonidas: [turns back shouting] Spartans! What is your Distro?
Spartans: FE-DOOR-RA! FE-DOOR-RA! FE-DOOR-RA!
King Leonidas: You see, old friend? I brought a better Distro than you did.
Fedora is a Linux-based operating system that showcases the latest in free and open source software. Fedora is always free for anyone to use, modify, and distribute. It is built by people across the globe who work together as a community.
Their latest release Fedora 11: Leonidas is available for download
