These are my general notes on configuring a Linux KVM server running on CentOS 6. Hopefully some day this will be complete enough to be in the Guides section.
Author Archives: Andrew Wells
Rename a Volume Group in Ubuntu 12.04
Ubuntu names the volume group according to the hostname of the computer, but sometimes I want to change it after the fact, and doing so is pretty easy.
Since writing this procedure, I did run into a reason why unique volume groups could be useful. I had a system crash, which required me to take the HDD and connect it into a working system. Both machines used the VG name of “system”, so this caused a conflict with mounting both VGs. In this case, I had to rename one of them to perform my data recovery.
CentOS 6 Deployment Server
This guide is an amendment to the Ubuntu Deployment Server. This guide assumes that you have a server similar to this setup. If you need to go through that guide first, you only need to complete up to Checkpoint Two.
To clear up any potential misleading in the title, this server is powered by Ubuntu 12.04, but will have the ability to deploy CentOS 6 to PXE clients. Why? Because I did that one first. No sense in re-inventing the wheel.
Improve Nagios Performance with TempFS
Converting a couple directories to tmpfs will significantly reduce disk I/O by Nagios for status updates.
PXE Boot any ISO Image
There are several rescue utilities out there that run in the form of a bootable ISO, but what if you already have a functioning PXE server and don’t have a CD? There is a way to load it over the network.
bashrc
I have a few customizations to the bash prompt and how bash interfaces with a terminal window.
CentOS 6 OS Install
Before I had my Kickstart templates created, I went through manual installs. This guide is here to remind me of some steps to keep consistent systems.
My Mobile (and Virtual) Deployment Lab Powered by VirtualBox
When I built my ESXi server, I learned how to deploy Ubuntu over the network using PXE and preseed files. I found it invaluable in quickly creating VMs for testing whatever I felt like tinkering with.
Over the summer, I was pressured to not have the G5 running 24/7 because of the excess heat. I have a Core i5 / 8GB RAM laptop that I figured I would put to good use. I added a high performance SSD in the optical drive bay (who uses CDs/DVDs and more anyway), and installed Virtualbox on top of Windows 7.
Nagios 4.x Install from Source on Ubuntu 12.04
I do not have Nagios 4.x on any production boxes yet, but I want to keep track on how this is working on Ubuntu 12.04. Apparently Nagios Core wasn’t well tested for Debian systems if at all. But in any case, it can be installed with a couple modifications.
This guide is going to be very similar to my guide on Nagios 3.x.
Update: Are you already on Ubuntu 14.04? Head on over here for the latest guide.
Nagios 3.x Install from Source on Ubuntu 12.04
When I deploy a new Nagios box, I always start with this. I do not use deb packages here because they are too many versions behind. Plus, I like to have full control over how this is configured.