Virtual servers - how specific a role...?

[BJG]

Bit of a vague question, but how specific do you tend to make your virtual servers...? For instance, I want to set up virtual servers for:

 

1) Antivirus (Symantec Endpoint Protection)

2) Video delivery (Clickview)

3) DHCP

 

Would three servers be overkill...? I guess there are two issues:

 

a) Cost of licensing

b) Efficiency

 

It's (b) I'm not sure about...

[localzuk]

In an ideal world, individual server for each role. Licensing and resources may limit you down though!

 

Reason being is that if you need to do maintenance or move something, you only take one specific service offline at that time.

[fairm010]

I tried hard to have a VM per role but as you said, Licensing really stopped me doing it. I have 3 VM's, 1 with WSUS and WDS, 1 with DHCP and DNS, 1 with IIS and AV database.

[fiza]

With EES I just got a DataCenter licence for my VM hosts so no problems loading them with Server VMs.

[PotNoodleTech]

Yeh if you've got EES with datacentre licence then you can crack on and split up us many roles onto as many copies of server as you want.

 

If you have not got EES and your paying ~£90 per Std Server licence then it may make sense not to split up the rolls too much. Maybe try to keep "similar" rolls on a server so that taking down one server for maintenance will only take down a specific system (rather than several systems) e.g DHCP can be on domain controller, print mgmt software can be on print server, pupil shared area on same server as pupil home drives, etc.

[BJG]

Yeh if you've got EES with datacentre licence then you can crack on and split up us many roles onto as many copies of server as you want.

 

Sounds good. We have an OVS-ES license; can't remember what the difference is. Out of interest, what kind of hardware are you running your VMs on, and how many per box...? Have you gone with SANs and stuff...?

[fiza]

Sounds good. We have an OVS-ES license; can't remember what the difference is. Out of interest, what kind of hardware are you running your VMs on, and how many per box...? Have you gone with SANs and stuff...?

 

We have started slowly. Got 12 VMs on the go at the moment with plenty of space for more. Personally wouldn't bother with a SAN. Locally attached drives working fine for me with Veeam taking backups off to a NAS.

 

Have 2 hosts so should one go down I can move all VMs to the other and vice versa.

[BJG]

OK, thanks for the pointers all. I'd be interested in current recommendations for any specific hardware.

[tmcd35]

On the subject of licensing...

 

...Getting Datacenter on EES may not be the cheapest option. Datacenter center on Volume Select isn't crazy money. You need to work out how often you plan to upgrade the host server OS to see if EES annual subscriptions are better.

 

We have EES for the desktop but by server licences perpetually because we don't want to upgrade every 3 years or so.

 

Either way Datacenter usually works out better value than Standard when you're virtualising.

[Sam_Brown]

One server per role and some back up built in so couple of DCs etc.

 

Like mentions above with a datacentre license world is your oyster.

 

Keep one DC physical though for obvious reasons.

[jaminben]

Keep one DC physical though for obvious reasons.

 

We're about to go 2012 R2 with vm's in the summer and thought about running two machines as the hosts with the 2x DC's running in a vm but both of the hosts would be non-domain machines. Every other vm host capable machine would be domain joined.

 

Does this sound like a bad idea?

[teejay]

Up to server 2008 R2 it was recommended that you kept one physical DC, that is no longer the case in 2012 onwards and you can happily virtualise all your DCs as its now fully supported with the changes Microsoft made to how Active Directory syncs.

[Sam_Brown]

It was more to do with the fact if for some reason your SAN \ VM Cluster should fall over or you need to take them down for maintenance you still have a physical DC available. I was thinking more from a disaster recovery point of view rather than a day to day usage.

 

Also to add to things not to virtualize one thing I've always been taught is to not use a VM as a NTP server as the drift on the VM clock is a lot worse than that on a physical server.