Virtual servers? How and why?

[Santilli]

Hi

I got a chance to look at a Virtual server setup that was REALLY cool. I'm just wondering why one would do it, and how?

Power savings is the first and foremost...

Thanks

Greg Santilli

 

[Stinker]

My thoughts are...

More servers in less space.
Less need for cooling the server facility.
Simplicity of maintenance.
Less physical hardware to maintain.
Better server availability.
Better load balancing of workload.

I have no IT background, however....

 

[MaxBurn]

I have a copy of windows 98 for some old apps that only work right under that OS. I also have another copy of XP for when I want to VPN to a remote machine on a customer site and still get stuff done locally.

I am mainly using VMware, the free version. I have had a couple of problems with it so not a perfect experience but it really is interesting to deal with.

 

[Handruin]

To answer your questions:

1.) Why?
First, see Stinker's points. He claims no IT background, but he's hit a lot of the major reasons. Many of these are exactly why I use virtualization is used in my current position.

In the rackspace of a 10U enclosure, I have the capacity to host upwards of 500 virtualized systems with redundancy.

Deploying a virtualized system from a template is ultra convenient from a system management perspective. There is also a concept of a system life cycle (from going live to its demise). A team member will come to me and request ten of machines for a given project which may be 6 months long. I can usually have the machines setup and ready in a day. I have access to multiple subnets in our network because of VLANs.

Hardware maintenance is a breeze. If I need to take a system down, I can move all virtualized systems off the hardware without anyone knowing it happens. I can do my maintenance and then bring the system back online and no one ever knew it happened. I recently upgraded 10 physical ESX servers (which requires 50 minutes down time each) without anyone ever knowing until it was completed. Once you actually spend some time in a larger environment and deploy and adopt a virtualized solution, you'll wonder why you ever used bare iron for everything.

Also, there is a concept of virtualized appliances. This is a nice way to deploy a set-and-forget system that is compatible with the different virtualization technologies (i.e. vmware, hyper-v, parrallels, etc). I could package you a solution and all you need to do is download the image and power it on with your virtualized environment and you have a full-blown appliance to meet your needs. One simple example could be a freeNAS, OpenFiler, or even SmoothWall.

2.) How?
There is a decent amount of planning that goes into this, but like anything it all depends on what you want to do. If all you want is 1-10 virtualized computers, you can do this very easily with several different types of solutions on a single computer like the one you have. You can create different OS to use for testing and sandboxing so that you don't harm your main machine.

If you want to deploy a larger environment like David uses or I use (maybe others, I don't know who else) you want to focus on a system that will be dedicated to something like ESX(i) (vSphere) or a dedicated Hyper-V system. You'll gain better performance and features geared for enterprise and medium to large businesses.

I've been using VMWare products since 2003/2004 (ESX 2.x) and I've not wanted to go back since then. If you want more examples or info, let me know.

 

[timwhit]

I use VirtualBox on my Linux machine to run Windows XP and Windows 7. TurboTax doesn't offer a Linux version, so I used the virtual to file my tax return. I haven't really used it for anything else.

We use VMWare ESX and ESXi servers extensively at work to run virtualized Windows and Linux boxes. We also use Solaris Zones for Solaris machines.

 

[Bozo]

Virtualizing an operating system just for surfing the web is much safer than using your main OS.
After you set up the virual OS, you copy the files to a safe place. If your virtual OS gets clogged up with viruses and what-not, just copy the original files back.
Keeps the main ( or host ) OS clean.

 

[ddrueding]

I mentioned virtualization to Greg after showing him the workstation backup capabilities of Windows Home Server. Considering Greg uses his "server" as more than just a file and backup server, running WHS as the only OS wasn't feasible. However, using a free tool like VirtualBox or VMWare Server to host a WHS machine, maybe even map some drives directly to it, seemed like a way he could check out WHS and even take advantage of the workstation backup capabilities.

 

[timwhit]

I mentioned Solaris Zones above, is anyone else using Operating system-level virtualization?

The Wikipedia article explains some of the advantages/disadvantages pretty well. But, if the point of your specific virtualization project is to have separate hosts rather than highly portable or highly available hosts it seems like a good option. You no longer have the problem of having to specify how much RAM or disk space each virtual machine gets. With OSLV, all hosts can share memory, disk space, etc.

For example, at work we have a Sun Fire T2000 with 16GB memory running Solaris 10, that is used as our development and staging environments. We have two staging zones setup that we use for business acceptance testing as well as for testing our load balancer. So, with one host we get 3+ virtual hosts, and we can share memory and disk space between them without worrying about memory allocation or disk allocation up front. We can also create a new zone in about 5 minutes (additional time to install app servers, etc). Rather than having to do a complete OS install to a new virtual machine.

 

[Chewy509]

I mentioned Solaris Zones above, is anyone else using Operating system-level virtualization?

I've used FreeBSD jails for testing in the past, but other most I've the stuff I deal with is either VirtualPC or VirtualBox to host individual OS instances for software testing.

PS. I've started reading about CrossBow with OpenSolaris, which is a pretty cool bit of technology.

 

[Sol]

We use VMs to distribute software to testers, during the development cycle the installer tends not to keep pace with the features so installing an alpha or beta release can involve a lot of messing around (Especially when the software is being developed by 6 teams on 4 continents). If we stick the whole thing on a Linux VM and hand that to the tester they just have to load in up and do some basic reconfiguration and they're good to go, plus each development team can install their bit of the software on the VM and pass it on making sure that the install was done right.

 

[Santilli]

What program would you recommend to run on Windows 7, on a 2 gig, Dual Xeon Box?

Free is good...

A program that only uses the resources when that Virtual box is up would be great.

I do have Windows 2003 sitting around, doing nothing, and, it would be perfect to run on a VM box...

Thanks

GS

 

[ddrueding]

I just installed VMWare Player on my workstation and installed a clean XP on for use with RockSim. Free, easy, consumes a small amount of resources 24x7, but they all do (the have to load their own device drivers, etc.)

 

[Santilli]

I just got this notice from Supermicro:

http://www.supermicro.com/products/nfo/dunnington_intel.cfm?gclid=CM6krvKp1KACFQ2lagod7XkXtA

new serverboard, DD;-)????

 

[ddrueding]

Most likely. That board is only $1k.

 

[Buck]

I just got this notice from Supermicro:

http://www.supermicro.com/products/nfo/dunnington_intel.cfm?gclid=CM6krvKp1KACFQ2lagod7XkXtA

new serverboard, DD;-)????

SuperMicro System: SYS-8045C-3RB

 

[ddrueding]

SuperMicro System: SYS-8045C-3RB

For $2k, not bad at all. A virtualization powerhouse.

 

[Santilli]

HMMMM. It even has a PCI-X slot for my SCA backplane and Megaraid card...;-)

The cat would be MUCH happier. Wonder if they still use the jet engine fans...

 

[Santilli]

DD:
Thanks for the link. Downloaded the program, and, now I'm thinking about it.

I might install it on the Beast. I might run an install of XP for some older games, like COD, that won't run on 7, IIRC.

I might install 2003 server on either the server, or the Beast, and, I have no idea why? Just because I can?

?????

I'm concerned with degrading performance on the Server.

On the Beast there appears to be major advantages to running old games on a Virtual machine, with the i7 horsepower, ram, etc.

There used to be these great games, Tex Murphy, that would run best on a mac, or an old version of windows. Too bad I didn't know about this
years ago. I would have kept the old OS and games.

Mac OS 9 on this hardware would be a REAL eye opener...

 

[mubs]

HMMMM. It even has a PCI-X slot for my SCA backplane and Megaraid card...;-)

The cat would be MUCH happier. Wonder if they still use the jet engine fans...

Why don't you just get a $30 heater for the cat?

 

[Stereodude]

Why don't you just get a $30 heater for the cat?

Because for every problem there is an inelegant and costly solution just waiting to be used. :beye:

 

[ddrueding]

Adding computing power is an elegant yet costly solution. At least you get to do something with the electricity before it becomes heat. And it's not like it is any less efficient as a heater...

 

[Santilli]

Adding computing power is an elegant yet costly solution. At least you get to do something with the electricity before it becomes heat. And it's not like it is any less efficient as a heater...

I have a VERY elegant cat. She is a Tuxedo cat, black with white paws.
She deserves an elegant solution;-)

 

[Santilli]

How can you tell if the connection is working?
I have a prior connection, allowing net access to the router, and, had
a common file. File transfers have been between 20-70 mb/sec, so, I guess the connection is there, but is there a way to make sure the file is setup on that connection, or, that the connection is maximized for speed?

I decided to remove the card that was blocking the fan on the video card, and replace it with the gigabyte 100 ethernet card.
Since the file transfers are nearly the same speed as writing to the hard drive, and most of the work is done on the beast, it seems to work fine.

All that is lost really is two removeable drive bays functioning.

Plus, I keep the cat happy...

 

[ddrueding]

The best way to make sure traffic goes over the dedicated crossover link is to use different IP addresses, hardwired without a default gateway, and access the share via IP address.

 

[Santilli]

The best way to make sure traffic goes over the dedicated crossover link is to use different IP addresses, hardwired without a default gateway, and access the share via IP address.

Figured with my rates it was going CAT5. Disconnected the cat5 cable during transfer, and this confirmed it.
Checked my ip addresses, deleted the default gateway, and off to 30 mb/sec or so.

Not sure what you mean by
"and access the share via IP address.[/QUOTE]???

 

[Santilli]

WOW!!!!
Three large file transfers sustained, at about 95 MB/SEC. !!!!!!

Don't need the moveable drives in the server much anymore...

 

[Santilli]

HMMM. Virtual fun. First installed from a valid windows 32 bit CD. Said I had exceeded the number of times I can load it.
Didn't care, so I loaded Quake 4 on it, it crashed, and stayed crashed.

Found out Blue Tooth keyboards are not the way to go for Virtual machines, so, added in a serial port MSFT keyboard.

I installed Windows 64 Pro. Came back the key was invalid. Saved by DD. Got the one off the back of The Beast, and we are up and running soon. At least the install is finishing.

Might be a kick if I might be able to make an iso of the Disk, and just see how fast it installs.

It's installing Drivers, and stuff right now, and, The Beast is cranked up to 3.11 GHZ

 

[Santilli]

HMMMM. Certainly is intresting having XP Pro 64 and Seven running at the same time..

 

[Santilli]

Been playing Quake 4 at Ultra High Settings. Can't load the video driver, and, it won't work with anti-aliasing turned on.

 

[Santilli]

Finding out fun stuff. MSFT has a virtual machine on 7 to run XP. However, no GL support
kills most of the reasons I would want to run XP on this box.

VMWare does support GL in their drivers, but, not as well as might be possible, considering the sheer horsepower of this Beast.

I'm finding my impression of 2000 is the same now as then, everything happens NOW.

It's taking awhile to find working iso's of the different os, and, it's real funny when MSFT tells me that my legally purchased key code for windows is invalid...VERY strange.
It even says that when I load my original 2000 CD on my machine. Weird.

No updates it seems for 2000.

Last day of support is JUly 16th 2010 or something???

I was toying with putting the MacOs on my box, but, why bother? With Apples' legal group, I'm sure they are doing all they can to keep people from trying it without paying for it.

I was considering trying to load OS 9, but, it's still Apple.

I really like being able to try, more or less, the OS and the game, or tool, without risking my basic machine. GOOD stuff.
Thanks

Gs

 

[Chewy509]

Finding out fun stuff. MSFT has a virtual machine on 7 to run XP. However, no GL support kills most of the reasons I would want to run XP on this box.

VirtualBox has OpenGL acceleration support for Windows, Solaris and Linux guest OSs. Direct3D acceleration is coming for Windows guests.

BTW, unless Virtual PC emulates a PowerPC CPU, Mac OS 9 isn't going to run on it?

 

[Santilli]

Chewy:
Thanks but, I'm just learning this stuff, and, the great thing about it is I can try 4 OS on Vmware, and, find out what works, and doesn't.
I just downloaded Virtualbox, and, I'll do the same with it...

Thanks for the link

 

[Santilli]

bump

 

[ddrueding]

What questions did you still have?

 

[blakerwry]

My thoughts are...

More servers in less space.
Less need for cooling the server facility.
Simplicity of maintenance.
Less physical hardware to maintain.
Better server availability.
Better load balancing of workload.

I have no IT background, however....

We've had some concerns with the availability and load balancing aspect of the equation.

First and foremost is availability, we're a hosted service provider. We often dedicate a physical server to a client. This allows us to ensure that a HW failure is not going to affect multiple clients. There's nothing worse than having all your clients calling/upset when something goes down - one is enough! This is probably our biggest concern, we like the diversity that having a dedicated machine, in a different rack, served off different UPSes, on a different breaker panel (or even a different physical location) provides. Putting all your eggs in one basket may reduce the number of eggs that break, but if/when that big egg does break, it's going to be a mess.

The second issue is workload balancing. We don't want one client affecting the performance of another. There are already shared network resources (to some extent), and I like the borders that having separate physical machines provides. If we provided virtualized servers, we would definitely need to allocate disk IO much more strictly - CPU and memory can easily be dedicated, but it's the disk and HBA that seem much less controllable in most virtualizing platforms.

Simplicity of maintenance is another area where I can find some fault. Being able to run a virtual host for each service/application and being able to run your old software on new HW has its initial appeal. That is, until you have to find updates for 10+ year old software, and have 50+ virtual machines to update. I usually find that the software needs updated around the same time as the HW resources. For this reason, the maintenance aspect hasn't been as appealing. I certainly don't want to end up with a bunch of out of date operating systems out of my own laziness because I've now separated the software from the machine and don't *have* to update them at the same time - granted, if this happens, it would be my own fault, but I bet it does happen more often in an environment that relies heavily on virtualization.

That said, you did nail the reasons, and even the ones that I have concerns about can probably be addressed in some manner. I'd be interested in hearing more from some of the folks that virtualize in enterprise environments. The main incentives to virtualize for me would be less HW to maintain and the ease of provisioning, backups, and migration to new HW. Because of the previously mentioned concerns, our virtualization has been limited to low priority applications that are used internally, and require few resources.

 

[ddrueding]

Isolating hard disk IO is important. The easiest way to do it is have a bunch of disks in the server and give the important VMs their own. Same with HBAs if you like, though I don't run into bottlenecks there as much.

Distributing your budget across a bunch of servers means each is more likely to fail due to cheaper parts (less redundant power supplies, non-ECC memory, etc). Going to fewer servers means being able to throw more money at each. More significantly, the more advanced VM platforms mean that a complete server failure doesn't actually ruin anyone's day.

 

[blakerwry]

Isolating hard disk IO is important. The easiest way to do it is have a bunch of disks in the server and give the important VMs their own. Same with HBAs if you like, though I don't run into bottlenecks there as much.

That's been the plan. Unfortunately, I think this is one area where virtualization undeservedly gets a bad wrap. People often consider CPU speed, RAM capacity, and HDD capacity, but tend to overlook RAM and HDD speed. People who deal with mail know that disk IO is everything, and are fully aware of the performance implications of putting two competing applications on the same storage.

Distributing your budget across a bunch of servers means each is more likely to fail due to cheaper parts (less redundant power supplies, non-ECC memory, etc). Going to fewer servers means being able to throw more money at each.

If you're going to dedicate CPU cores, RAM, and disks to each virtualhost, you've ended up back where you started - lots of pieces, lots of money, etc. Sure, there are some shared parts that are not duplicated (Chassis, power supplies, etc), but the bulk of the cost is back. But you are right, we are budgeting more money to maintain more hardware. But, the hardware really isn't the bulk of expense anyway - its costs are made up relatively quickly.

More significantly, the more advanced VM platforms mean that a complete server failure doesn't actually ruin anyone's day.

I love the features that virtualization + SAN can provide, unfortunately we've seen SAN based service providers have outages and performance problems that we simply haven't experienced with DAS. As long as DAS meets our scalability needs, I feel it is the fastest and most resilient storage method when configured appropriately. It is certainly does not have the flexibility or scalability of SAN, however.

 

[ddrueding]

That's been the plan. Unfortunately, I think this is one area where virtualization undeservedly gets a bad wrap. People often consider CPU speed, RAM capacity, and HDD capacity, but tend to overlook RAM and HDD speed. People who deal with mail know that disk IO is everything, and are fully aware of the performance implications of putting two competing applications on the same storage.

In my environment here there are many servers that are nowhere near HDD bound. In fact, they don't really stress anything. Putting them on a single basic box is a direct cost savings. Those that are HDD IO limited can share the rest of the box with these machines so long as they get their own storage.

If you're going to dedicate CPU cores, RAM, and disks to each virtualhost, you've ended up back where you started - lots of pieces, lots of money, etc. Sure, there are some shared parts that are not duplicated (Chassis, power supplies, etc), but the bulk of the cost is back. But you are right, we are budgeting more money to maintain more hardware. But, the hardware really isn't the bulk of expense anyway - its costs are made up relatively quickly.

Not so. Getting 6 cores in a machine is considerably cheaper per core than 3 dual-core machines. You also don't need to plan for 50% headroom to accommodate peak loads; it is unlikely that all your VMs will spike at the same time, so 15% headroom is usually fine. Even with only 15% headroom, each machine has access to more horsepower when it needs it than it would otherwise.

I love the features that virtualization + SAN can provide, unfortunately we've seen SAN based service providers have outages and performance problems that we simply haven't experienced with DAS. As long as DAS meets our scalability needs, I feel it is the fastest and most resilient storage method when configured appropriately. It is certainly does not have the flexibility or scalability of SAN, however.

I still use DAS myself. Simply replicating the entire VM to another VM server allows ~5 min downtime before we are up again. That is plenty for my needs, and way better than you will get on dedicated machines.

 

[blakerwry]

In my environment here there are many servers that are nowhere near HDD bound. In fact, they don't really stress anything. Putting them on a single basic box is a direct cost savings.

This is the situation where I can absolutely justify virtualization. There's potential wins all over the place with little or no downside.

...

Not so. Getting 6 cores in a machine is considerably cheaper per core than 3 dual-core machines. You also don't need to plan for 50% headroom to accommodate peak loads; it is unlikely that all your VMs will spike at the same time, so 15% headroom is usually fine. Even with only 15% headroom, each machine has access to more horsepower when it needs it than it would otherwise.

We're already buying 16/24 thread systems for our non-virtualized systems ;- )

The situation you mentioned above with lightly loaded boxes is where I can see a valid comparison between a single 6 core machine vs three dual core machines. Except that we usually have enough "hand me down" hardware to fulfill the need for the light load boxes. Having to maintain the older hardware is more of a concern there than anything else, eventually power and heat will become a bigger concern.

I still use DAS myself. Simply replicating the entire VM to another VM server allows ~5 min downtime before we are up again. That is plenty for my needs, and way better than you will get on dedicated machines.

That would be nice. I assume without a SAN/NAS you have to shut down the VM, rsync the data to the destination server, and then import the VM on the new server?

What happens if there is some failure of the current host VM and the data cannot be transferred? restore from backup? snapshot? Do you create and archive snapshots of each VM?

 

[ddrueding]

Veeam software allows online, real-ish time replication. Works great.