vmware or spare harddisks for "occasional" server?

[pete]

We have a handle of exams software and other cruft that Does Not Play Nicely With Others. Unsurprisingly, these mostly require IIS and my two IIS boxen do Important Things, so I'm loath to install the software on them and I have KS3 Tests knocking on my door soon.

 

My server room is crowded, with approx 3 more servers to go in.

 

I was thinking of buying a server and using a separate vmware instance for each app with spare images in case it b0rks. Do webservers on Intranets incur cals at any point?

 

I've played with the free vmware server and like it - is anyone using it full-time in production?

 

Of the folks who use ESX, what benefits does it give me from a maintenance / sysadmin and end-user perspective? Did you get edu discount? How significant is the performance boost vs running vmware inside another OS? Can you (automatically) allocate spare ram / processor if a server instance is being thrashed without rebooting the image? We can't afford a SAN, btw.

 

Cheers

[DMcCoy]

Each seperate VM will require licenses for various things, although if you have Server 2003 enterprise I believe yor are allowed to run 4 virtual instances of 2003 on each physical box that has an enterprise license, I would assume you need additional cals though.

 

I don't see why webservers would need any cals, but its something to check as we all know how microsoft are about these things.

 

I am running 6 ESX blade servers, it is not cheap - although costs have changed slightly recently with the introduction of version 3. I am still in the middle of a five month battle with dell to purchase my maintenance for the year - and now the new version is out, yet I seeming still have no maintenance, possibly meaning that I missed the upgrade. Still thats for me and Dell to work out.

 

It has its limitations, but its working well here. Would I do it again? Yes, whilst knowing this years budget? Perhaps not.

 

You really need a san to get the most out of it though

[pete]

@DMcCoy

most of the stuff is site-licensed and they won't be running anything but vanilla 2003, AV and the app in question.

 

Re Server 2003 enterprise

useful to know, thanks

 

Re CALS

I was idly wondering at what point it stops being a web server and becomes an application server that incurs cals

 

Re Cost

I'd love blades, but we can't afford blades. My plan is to have standard dual cpu hardware where I can keep everything sandboxed in virtual images and increase or decrease their available resources depending on time of year without them breaking anything else. The downside of my plan is multiple servers depend on non-redundant (apart from psu) hardware, upside is cost per server. Given that the only server failures we've had in 3 years were due to lightning (which only blew a NIC) I think its a pretty safe bet. *touches wood*

 

Re San

Yeah, I've been reading up on the cool stuff we could do with it Can't afford it ATM. This is more of a proof-of-concept - "Do virtual servers do what we need in our environment and can they do it better?" If it's a success, then there may well be cash available for a san come the time we refresh our main server hardware.

[CyberNerd]

The downside of my plan is multiple servers depend on non-redundant (apart from psu) hardware,

 

not really a downside, you can save vmware images and transplant them to another server, this improves uptime because moving a vmware image to a hastily constructed 'server' is much faster than reinstalling/reimaging. IIRC ESX server can do this live, whist the server is running.

 

My recommendation sans-san is to put teh vmware partition on separate disks. I use linux XFS as a filesystem as it seems to deal nicely with large files (the vmware images). Linux as a host is a good choice because it can run with less services running thus freeing more ram for the virtual servers, (even without a gui) and is particularly well supported on the vmware forums.

[pete]

@cybernerd

out of interest, what made you choose xfs over jfs? (not trying to start a holy war - last time I checked jfs had the edge over XFS for mythtv-style large file handling).

 

Does ESX play nicely with exotic / new hardware?. I'm assuming their bare-metal OS layer is something *nix based?

[DMcCoy]

Does ESX play nicely with exotic / new hardware?. I'm assuming their bare-metal OS layer is something *nix based?

 

No is the simple answer. If its not on the HCL then its not supported, and often will not work. Despite the ESX console being redhat 7.3 based, the custom vmware kernel that takes over druing system boot is not and this cannot have drivers added or removed unless by vmware themselves.

[CyberNerd]

out of interest, what made you choose xfs over jfs? (not trying to start a holy war - last time I checked jfs had the edge over XFS for mythtv-style large file handling).

 

TBH it was because someone suggested XFS, I checked the VMWare forums and it seemed a sensible choice. I've not really followed JFS/XFS debates but probably JFS would also be a good choice, especially now IBM are supporting linux.

[pete]

@DMcCoy

just looked the hcl over - the things that are listed as fully supported pretty much cover what I would buy anyway. I'm surprised 3Ware cards aren't mentioned but apart from that...

 

I'm thinking of 2U dual xeon @3Ghz (or opteron equiv), 4gb ram (if I can afford it) and SCSI disks. Not sure about raid yet because I'm not sure what the best performing config would be with vmware images.

 

@cybernerd

did you mean putting each image on a separate physical disk?

[CyberNerd]

did you mean putting each image on a separate physical disk?

 

If you can afford it

We've not done that here though.

[DMcCoy]

@DMcCoy

just looked the hcl over - the things that are listed as fully supported pretty much cover what I would buy anyway. I'm surprised 3Ware cards aren't mentioned but apart from that...

 

I'm thinking of 2U dual xeon @3Ghz (or opteron equiv), 4gb ram (if I can afford it) and SCSI disks. Not sure about raid yet because I'm not sure what the best performing config would be with vmware images.

 

 

3ware cards are most likely not supported because esx will not allow you to use ide or sata for virtual machine images, the only choices are SAN or scsi. You can't store more than 16 or so vms on a single disk volume due to scsi reservations.

[pete]

did you mean putting each image on a separate physical disk?

 

If you can afford it

We've not done that here though.

 

Hmm, probably not. Given the usage patterns of these apps (distinctly seasonal) I may be able to ensure that only one vm is running from any given disk at the same time.