James B. Byrne wrote: > On Fri, May 27, 2011 14:36, Jack Bailey wrote: >> 1. Get more out of your existing resources: Pool common >> infrastructure resources and break the legacy “one application >> to one server” model with server consolidation. > > I have difficulty with this statement on so many levels that it is > hard to know where to begin. Perhaps the most egregious is the > mindless equating of server with host. What measurable benefits > accrue to a firm from 'breaking the legacy', whatever that means. It looks like you are not familiar whit this model of business. Let say a company buys one design system that includes server backend and continuous support. Since they are responsible for entire environment, and in fear of admins braking anything by upgrading, and fearing that additional roles of that server might impair their product performance wise, they demand separate server just for that role. This happened 4 years ago, and was paid some, lets say, $550.000. 7 years ago accountants purchased a software product with their own database server. Same conditions, nothing else can be run on it. Let say that company that sold accounting software went out of business. Their product still runs perfectly on ancient "Red Hat Linux 7" server, but it is compiled for against gcc and other libraries from that time. Any change could brake that app. And hardware is for one old and it is not known if it will last a year or so, HDD's might fail and MB does not support modern ones. And RHL 7.x has no drivers for modern hardware. What to do? Virtualize both systems on strong modern hardware. You will get safe hardware for your ancient software and you will even get better speed and users will be much happier. > >> 2. Reduce data center costs by reducing your physical >> infrastructure and improving your server to admin ratio: >> Fewer servers and related IT hardware means reduced real >> estate and reduced power and cooling requirements. Better >> management tools let you improve your server to admin ratio >> so personnel requirements are reduced as well. > > Personally, my experience is that, if anything, running multiple > systems on a vm host measurably increases the administrative burden > per host. For one thing, you now have multiple instances to update > and to keep secure whereas before you had one OS to worry about. If > we had tens or hundreds or thousands of servers then yes, I can see > the benefits. We, however, do not deal with equipment on that > scale. Here they are saying about number of *hardware* servers/hosts and people needed to service them, to keep them running. If you have 30 servers now, you need to update all of them weather they are virtualized or not. But if you move them to 2 strong VM hosts, you admins will not have to worry about 30 PSU's, 30 x X HDD's/RAID volumes, your Power consumation will drop lets say 10-20 times, you will not need 30 strong UPS's on few gigantic. You will also avoid several heavy duty network switches, and performance wise network traffic would be visualized with enhanced speed. > >> 3. Increase availability of hardware and applications for >> improved business continuity: Securely backup and migrate >> entire virtual environments with no interruption in service. >> Eliminate planned downtime and recover immediately from >> unplanned issues. > > I suppose that moving VM instances as file systems provides a real > value by eliminating the setup and configuration required to get > bare metal to flash up in a usable fashion. This is in fact the > only area that I see a real advantage to VM over bare metal > installs. > >> 4. Gain operational flexibility: Respond to market changes with >> dynamic resource management, faster server provisioning and >> improved desktop and application deployment. > > I have no idea how deploying VMs to a company's desktop workstations > could possibly benefit the firm., Here is real world example for a small company with 20-30 workers. This was 3-4 years ago, in my Linux server beginnings. All they have known so far is Windows XP. I got a job to provide new Access database server (don't ask). I wanted to give them cheap RAID capability so I used integrated nVidia SATA RAID 1 with 2 HDD's and since server had to be Windows (XP Pro so I do not brake a budget, they accepted RAID without real understanding what it is), and they are now stuck the whole time with crappy RAID drivers and braking the RAID from time to time. That "server" is also used as Windows desktop for owners wife for Access accounting, Electronic payment etc... When CentOS 6 is out, I intend to install it on bare metal, add some RAM, set software mdraid RAID 10 and move already set Win system to VM (I know how to reset HDD drivers). She will be able to use her familiar desktop and apps, and I will be sleeping much better not thinking what will happen if servers MB dies and I am stuck with non functioning HDD's. The I will teach her to use Linux for net surfing and USB flash plugging/copying so we avoid possible viruses. What is more, if you need to get someone to test some new OS/software/combination, what better way to do it then installing VM image onto his desktop so he can use his current system for productivity and to test new software without braking anything or thinking about 2 keyboards and mouses, space to place new bare metal system, etc.. You can even install same image (install once use many times) on numerous desktops and can even install several VM's with competitive products without any hassle about braking something. You can have few hundred people simultaneously testing several products and at the end of the day they can still do their jobs on your original system. And if you can update/replace those VM's with new versions as fast as you can copy them over the network remotely, without physical presence of and admin, thus having lesser people on the support staff. > >> 5. Improve desktop manageability and security: Deploy, manage >> and monitor secure desktop environments that users can access >> locally or remotely, with or without a network connection, on >> almost any standard desktop, laptop or tablet PC. > > Again, how is this accomplished and what are the advantages over a > single OS install? None of the above claims have anything to do > with VM per se as far as I can see. > Breach of access to flash/floppy/DVD-RW comes to mind. Even encrypted file system on Linux (VM data is protected inside) while they actually then run and use insecure windows guest. Ljubomir