Small to medium business and Virtualisation/Virtualization
Posted on 2009-02-09
Currently we have an aging SBS2003 OEM Server. The biggest problem is that it being OEM makes disaster recovery difficult.
1) It need identical hardware to recover to. So should the active server become destroyed I need an identical one to restore to.
2) OEM Licence means that a whole new SBS2003 would be needed on a reserve server should original be destroyed as the OEM licence dies witht he original server.
As you can imagine it's difficult and expensive to implement.
Now, I'm a massive fan of virtualisation. I enjoy playing with virtual machines in Vmware, Parallels and Virtual PC software. I have also had a play around with OpenVPS for linux and have a hosted VPS online to play with.
Now I have a vision:
1) To have a ma,moth server with lots of cores and memory and base operating system. Would like to have linux as it would work out cheaper but due to my lack of linux knowlege for a working environment may need Windows server as base system. Whenever I upgrade or replace the server I can simply drag (copy) the virtual servers to new hardware and they work in a plug and play style only having to worry about having a host OS and virtualisation software installed. I would also beable to just keep several system states during system upgrades etc to be able to restore to any one.
2) Instead of SBS doing exchange, DC and sharing I would have several virtual servers running on the main server doing each job. This would mean that hardware compatibility for recoveries would be a thing of the past as the virtual machines could be restored on any hardware as long as it's running the virtualisation software. For example I could reboot the DC and not worry about the exchange server needing to be rebooted also.
3) I expect to only have to backup a single file (Virtual hard drive) instead of worring about mailboxes and data and settings etc. For example, if a Virtual server OS dies. I simply ge the backed up hard drive and copy it back to the host server. So I would restore the virtual server to a different computer and extract what data I need to restore to the live virtual server.
4) If hardware dies, I simply move the virtual servers to another machine, this would be non-hardware specific. And the only recovery time is the time it takes to copy the backed up virtual server from the backup location to the new/temp hardware
5) If I suddenly decided I wanted to run everyting offsite from a data center I just need to move the virtual machines to that location.
To be honest I'm very excited about the propect but I have 3 major queries that I don't know if they are problems that actually exist or rumours I have picked up.
1) Cost - Is it true that I will need to buy full OS licences for each virtual server I run? This would mean running linux for the host OS would help keep the cost down. Or are are there virtual licence schemes out there to make it cheap to buy licences for virtual machines? Or buy a scheme where you buy the host licence and get virtual licences free/cheaper.
2) Speed and latency - now as it's all running virtually, I know virtual machines are getting faster and the link between VM -> Host OS -> Hardware is getting better, but would I notice a massive dip in performance when running virtual machines so much so that the cost of the hardware can't justify the slow performance of each virtual machine. I unstand what quad-core and higher processors will help speed things and surely the performance hit wouldn't be comparable to our current Pentium Xeon single core 3.0ghz server.
For example I would expect to run 1 Domain Controller virtual server with shares and 1 Exchange virtual server, then possibly a linux server for FTP/filesharing etc all on the same hardware. Is this going to hurt the server speedwise or will it be an even trade off for resources between the 3 and I can just keep upgrading the hardware without worrying about the effect on the virtual server drivers etc.
...even if I didn't run multiple virtual machine and still ran SBS in a virtual machine instead of standard MS server would a single virtual machine on a host OS not get the full benefits of a single natively installed OS?
3) Virtual hardware support. Will microsoft and other os manufacturers all fully support virtual hardware in future. Will using virtual servers mean that I would have more in common with other administrators online as our hardware is no longer an issue other than having it work or not work, ie we're all running the same hard ware? for example, network cards etc.
Before getting anyway near to purchasing any kit. I will have to do a full case study of the options and costs, but any hints so far from administrators who have already implemented this or are looking to implement such a set up would be great.
I would love for the specific hardware on my server to no longer be a problem in disaster recovery. I like the flexible option of literally being able to run a virtual server on any hardware no matter what changes are made, upgrades occur etc.
Hopefully I haven't rambled on too much for a quick question!
I would be extremely insterested to hear you views on virtualisation in the small business environment.