On Mon, May 10, 2010 at 1:15 PM, Les Mikesell lesmikesell@gmail.com wrote:
On 5/10/2010 11:37 AM, Ross Walker wrote:
I have ESXi hosts here running 20 VMs per host with some doing terminal services, some doing email, some doing database and other network services and I have not noticed any diminished performance, and yes going virtual is simply the easiest way to perform upgrades.
I think it is unfortunate how difficult it is to back up a working linux machine and restore it onto different hardware, given that the system really is very hardware independent. But, detecting the hardware and mapping it to device drivers seems to be a black art hidden inside of anaconda and then the local hardware related settings are fairly hopelessly intertwined with application and user preferences in your backup copies. I always thought that this would be a common enough problem that some distribution would address it, but so far it hasn't happened.
That's why God invented the systems administrator!
Here I use kickstart scripts for baseline server types that perform all the basic configurations on install. Then I typically keep the server-centric config in a common location, /etc/<servername> and use symbolic links to the system supplied config, this can also be scripted for quick recovery. I keep the application data on separate volumes then the OS (typical OS image is 8GB, most is swap) using iSCSI so I can connect to them from another VM easily enough (RDM or direct iSCSI), everything is installed via RPM, if the distro repo version isn't adequate I build my own and keep a custom in-house repo, no third party repos.
I have yet to look at Cobbler which is suppose to simplify the creation and management of all these kickstart scripts and provide a nice interface, but haven't had the time yet.
If I am setting up an ESXi infrastructure the first thing I would do is setup a Cobbler server and a Windows deployment server (maybe a Solaris Jump Start server) and integrate it with the VMware vCenter templates. Then it's all point-n-click server deployment from there.
-Ross