Zoetrope

Excited about the load balancing, auto-scaling and other new features coming to Amazon EC2?

Here's a script to bootstrap a lean 32bit Centos 5 into m1.small AMI-form for use on EC2. I started with the Rightscale scripts and removed the interactivity and RightScale specifics and added some features: it's using a mirror based yum config to do a base install and I added the same scripts you can find on the Fedora AMI from Amazon itself to update the ec2-ami-tools and kernel-modules. I also included a couple of Dag's packages like dstat and others from RPMForge

Insert your AWS specifics in the top of the file, choose a bucket to store the bundles AMI in, and give your image a nice name. To bootstrap just launch a Fedora 8 instance (use ami-2b5fba42), copy over the script, your certificate and key, and run the script. With some luck - and no boobo on my part - you should see this in your terminal at the end:

Done! Put a fork in it!

Baking the AMI can take a while, so be patient. Afterwards you need to register this AMI so it shows up in your ec2-describe-images -o self command:

ec2-register your-bucket-name/image-name.manifest.xml

This is currently for a 32bit m1.small AMI only, I'm hoping to use some kind of template system to be able to bake a similar script for 64bit and 32bit AMI's alike.

The script:

http://zoetrope.s3.amazonaws.com/Centos5_X86_EC2_install.sh

(Re-)Installing Linux on a bare-metal Dell Poweredge server using CD's/DVD's is so passé. Instead use your servers network card to perform a PXE-boot and install it over the network.

Since all Dell Poweredge servers come with an IPMI BMC controller you can do this remotely from the office on a server in your datacenter. This how-to covers a remote install of a Dell Poweredge 2850 with an IPMI 1.5 BMC controller. This means we will use Serial-Over-Lan console redirection through a proxy program called Solproxy. If you've got a recent Poweredge server this step is not necessary.

This post assumes you have a working RHEL5/Centos5 install to serve as your provisioning server, and your bare-metal server has a working IPMI configuration. See this post by Lone Sysadmin how to configure the BMC on a Dell Poweredge if you have an OS running on it. Else you need to configure the BMC controller in the BIOS.

Here's how you use Cobbler to manage the TFTP boot server and DHCP server, and optionally build a mirror for several distro's from installation media or rsync mirrors...

If you're using http://rpmforge.net/ or Dag RPM packages you might have noticed there seem to be some problems with the mirrors. A quick snoop on the mailing-list shows us the reason from Dag himself:

HEAnet is having problems again. For some reason they still offer files 
(repoview) that have been removed a few weeks back. And for some reason 
they did update the metadata but not the packages (which cannot happen if 
the update process was using --delay-updates). And that is in this case 
the result of yum trying to update packages that are not available (while 
they should have).

I think they once again have major NFS problems.

But, I have no access to that system and that system is used by all 
the other mirrors. So we are basicly doomed... until it gets fixed.

Dag Wieers' Dstat is the ultimate live monitoring tool to catch your servers in the act.

My favourite Dstat command:

dstat -l -c -p -y -m -p -d -n

Which will paint this pretty picture on a wide-enough terminal:

Note the periodical repeating header at the bottom! Dstat is even smart enough to truncate the columns if your terminal can't handle the heat because it's to narrow - marvelous...

Booting RHEL 5 or Centos 5 for the first time in Parallels Desktop (build 3188) wil get you an instant kernel panic. Just include agp=off as a kernel parameter and the system boots and works like a charm (use 'a' at the Grub screen to edit the kernel parameters).

Afterwards you can edit the /etc/grub.conf to include agp=off by default:

 
title CentOS (2.6.18-8.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-8.el5 ro root=/dev/VolGroup00/LogVol00 rhgb quiet agp=off
        initrd /initrd-2.6.18-8.el5.img