Worth considering virtualization if you can't afford SAN?

walnuts

walnuts

walnuts

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Currently in the situation where 4 servers need replacing and wondering if virtualization is the best route to go down.

Servers need replacing:
1 x File Server (70 users)
1 x Blackberry Server (5 users)
1 x SQL Anywhere Database Server (5 users)
1 x P2V legacy ERP Server (5 users)

Main reasons for looking at virtualization is to reduce power consumption (currently have 22 servers), better utilize more powerful new servers you can buy and get advantages of virtualization (DR, snapshot etc).

What are people experiences with running virtual servers on local storage (RAID 10) or on a DAS?

Appreciate any feedback.

Shazad
 
If its quite a busy file server, please don't virtualise it!

We have one at work, it is terrible. If one person copies to it, everyone looses connectivity!

Worth having a standalone box for that purpose anyway :)

walnuts said:
What are people experiences with running virtual servers on local storage (RAID 10) or on a DAS?

Appreciate any feedback.

Shazad
Click to expand...

We also have VM's running on RAID10. Works well! Can even use SATA disks for that, but SAS is always better!
 
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Runing on DAS is fine. What you may lose however is the ability to swap vm's around servers easily.

This is an advantage of a SAN over DAS.

If you are strapped then may be worth looking at Openfiler. This converts generic PC hardware into an iSCSI SAN box.

With OpenFiler SAN then I can vmotion servers between my 3 ESX servers no problem.

Storage Servers are not the best option for virtualization however, as they are Disk I/O and most VM solutions are not Disk I/O friendly yet.

The latest 5500 Xeons and Intel NIC's and Chipsets supports VMWares direct i/o which improves performance of virtual storage however you do need the latest and greatest hardware to support all of the vmware esx4 or vsphere features.
 
From Hyper-V training course I got the impression that if your virtualizing a file server best setup would be to store OS on RAID 10 local storage and then use pass-through disk for file shares. I was looking at fibre attached DAS for this.

I will need to look further into this but I probably go with safe option and virtualize other 3 servers.

Thanks for feedback.
 
Nothing wrong with virtualising a file server IMO, especially with only 70 users.

I have about 85 users and virtualised:

- File server
- Exchange 2007 server
- SQL 2000 Server
- Progress server (big db!)
- Citrix servers
- Domain controllers
- MySQL server (2 factor auth)
- 2 x ISA servers
- Search server (microsoft search server express)
- SMTP server (mimesweeper)
- Citrix gateway and web interface
- Telephony reporting/logging server
- Document generation server
- Linux web server
- Virtualcenter server

All onto 3 hosts with 2 x Quad core Opterons and 16gb RAM.

Performance is nothing short of superb - you could achieve similar results with local storage just loosing the benefit of having the SAN.

I'd be comfortable with the servers you list on one host and decent local storage - some people's views on virtualisation still seems a bit outdated

CPU usage across the cluster:

46995960.jpg
 
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Ringiho said:
If its quite a busy file server, please don't virtualise it!

We have one at work, it is terrible. If one person copies to it, everyone looses connectivity!
Click to expand...

Sounds like someone has madea HUGE cockup of the implementation of that
 
Fair enough - there's no way that should happen.

File servers, generally, have quite basic requirements. CPU and memory arent really a problem, ancillary processes such as AV and backup will use more of that. The other 2 are more of an issue with a file server - network throughput and disk IO. Both can be carefully monitored post virtualisation in order to plan an effective strategy. In an 85~90 user environment we were barely touching the NIC and disk IO was relatively low too - this lead to the decision that it would share the bonded gb NICs on the hosts and also just use a vmdk on a shared RAID5 LUN (for data, system drive is on a shared RAID10 LUN).
In higher usage environments, you could happily dedicate a NIC if you needed and put the data on an RDM on it's own LUN - no impact at all over physical. I wouldnt expect to see either of those being necessary until you reach over 500 users (ish) - depending on the usage obviously but I'm talking about a straight office environment
 
Don't know why everyone is against a virtual file server?

Ours is fully virtual on RDM LUNs.

2.5k users and 2.2TB of live data.

2VCPU's and 4GB of RAM. CPU Average is 31% and disks are currently RAID5 10k FC. I/O never goes above 600 anyway so could move to SATA easy without issue :)

Network usage averages 4.5k KBps and shares bonded GB NICs with about 12 other production machines :)
 
We virtualise a file server for ~100 users here, fairly low I/O requirements but it is FAST, and we're not using SAN.

Once you get lots of users, SAN becomes a requirement but at the level you are talking about you CAN do it with local storage and it will be fine.
 
DRZ said:
We virtualise a file server for ~100 users here, fairly low I/O requirements but it is FAST, and we're not using SAN.

Once you get lots of users, SAN becomes a requirement but at the level you are talking about you CAN do it with local storage and it will be fine.
Click to expand...

Are you using RAID 5 or 10?
 
I had my virtual file server running on local storage before the hardware upgrade - was on RAID5 with 15k U320 disks - was happy as larry.

My setup is currently iSCSI - I've been given various different figures for the FCAL "cutoff" point. Dell told me 42 disks and above makes FCAL worth it and HP told me 15 VMware hosts.

Either way, for small deployments, FCAL is not even worth spending time considering - for medium/large deployments I'd put serious thought into it
 
Virtualise everything.
Its not just down to the Virtualisation layer, its about the network and way you design and configure the storage.
We use ESX 3.5 with Falconstor's IPstor product to virtualise a Hitachi AMS1000 san with 15 shelves of fibre channel disk and SATA for tier 2 storage, on that we have Exchange, file servers, DB servers and app server guests serving 450+ users.
DAS is as good as local storage but a good RAID card is a must.

Im looking at using 2 DL385 G5p at each of our remote sites using ISCSI SAN software so we can move guests around automagically in event of hardware failure - each box has 8 x 146gb SCSI disks, 2 x quad core AMD and 16gb RAM - performance is very good, way better than the outgoing DL380 G4s there replacing.
With the DL385 G5p you can have additional 8 disks giving 16, thats a good chunk of IOPs!

http://communities.vmware.com/docs/DOC-8760 - Fantastic ESX script that backups Vm's on the fly with no down time, thin provisioning so the backed up size is only what the disk is using rather than the whole disk size.

http://www.rocketdivision.com/wind.html - ISCSI target and initiator - useful free version for presenting disk to ESX and other servers.

http://www.phdvirtual.com/component/jdownloads/?task=view.download&cid=10 - Free ISCSI SAN, simply awesome. Two nodes only for now, 4 in Q3/Q4 this year. < very good free option.

http://www.compaq.com/storage/highlights/lefthandsans.html - HP iSCSI SAN solution, good support and with special bid comes in at 2.4k per node and you can have upto 4 nodes.
 
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