brucefan
1 Nickel

PS4000 Equallogic CSV speeds

I'm pretty new to SANs so bear with me.  We just got an Equallogic PS4000X with 2 R710 Poweredge servers with the intention of clustering the servers using them for Hyper-v implementation.   The R710s are running Windows 2008 R2 Core...clustered with the Equallogic (Raid 10 with SAS drives) through 2 stacked Dell 6224 switches.  2 iscsi ports per server and using the Dell HITKIT 3.4.2.    We created 1 - 500GB volume and set it as a Cluster Shared Volume and a 100GB volume and did not set it as a CSV...just using it as a basic failover volume.    We then set up 2 VMs (Win 2008 R2 standard with nothing loaded...only joined to domain)....one with the VHD files on the CSV volume and one with the files on the standard volume...both on the same host, both using same virtual NIC. 

 The issue we're seeing is with file copies to and from the server that's on the CSV.  From a PC or server on our domain....copying files to the server that's on the standard volume results in about 100 - 110 MB/s speeds.  Copying files to and from the CSV VM server results in about 25 - 30 MB/s.  So far support is telling me this is "normal"....but I'm having a hard time believing that.  Before I ditch CSV altogether (I can't see hosting any servers...file servers or application servers...with these kinds of speeds)....can anyone tell me if this is in fact normal behavior??  

What I've tried:  Enabled jumbo frames on switches, nics and servers, enabled flow control on the switches, turned off STP, changed the NIC bindings on the servers, disabled "File and Print sharing" on the iScsi nics. 

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7 Replies
Dev Mgr
5 Rhenium

Re: PS4000 Equallogic CSV speeds

Check if the CSV is owned by the same cluster node that owns the VM. If not, move one of the two over and see if that makes a difference in the performance that you're measuring.

Member since 2003

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brucefan
1 Nickel

Re: PS4000 Equallogic CSV speeds

The cluster is only 2 servers so I copied the CSV VM onto both hosts with just different hostnames...no difference.

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Dev Mgr
5 Rhenium

Re: PS4000 Equallogic CSV speeds

CSV allows you to have the disk (volume) owned by one host (physical server) while a guest (VM) on there is owned by a different host. To allow this to work uses the CSV network link. If this link is slow, your disk access is slow. Moving the guest and CSV onto the same host means it doesn't have to go through the CSV link to be able to write to the disk, and therefor it may be faster.

This is why I asked if you had verified if which host owns the CSV and if that's the same host that owns the guest that you're testing performance on.

Member since 2003

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brucefan
1 Nickel

Re: PS4000 Equallogic CSV speeds

Sorry...should have elaborated.  The reason I copied the VM to the other host is to rule out a host issue...so it was tried on the one that hosts the CSV as well as the other.   So each host has a VM on the CSV that is slow. 

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Moderator
Moderator

Re: PS4000 Equallogic CSV speeds

BruceFan,

Hi, I'm Joe with Dell EqualLogic.  Not sure if you had a chance to review the following:

http://www.equallogic.com/resourcecenter/assetview.aspx?id=7787 (Deploying Microsoft® Hyper-V™ with Dell EqualLogic™ PS Series Arrays)

And the FAQ: http://www.delltechcenter.com/page/Hyper-V+R2+CSV+FAQ

In the deployment gride, in Table 3, it lists the following: "Best practice recommendation requires additional adapters on each server in the cluster for CSV related traffic", and in the FAQ there is a link to the Microsoft validation wizard.

I think your problem relates to the "bandwidth" and not the array. In the guide I referrenced, it clearly states  the following:

The Hyper-V™ server should have two or more network adapters depending on the use cases for the NICs. One dedicated NIC should be configured for remote management of the physical server and one or more NICs should be configured for virtual network traffic. Additional network adapters will be required when connecting to iSCSI SAN volumes and Failover Clusters including a dedicated NIC for VM Live Migration if using CSVs.

After reviewing this informaion, please post any other question you might have.

Regards,

Joe

-Joe

Social Media and Community Professional
#IWork4Dell
Get Support on Twitter - @dellcarespro

Follow me on Twitter: @joesatdell 

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Highlighted
brucefan
1 Nickel

Re: PS4000 Equallogic CSV speeds

If it was bandwidth, I would think I'd see the issue on the non CSV volume as well as the CSV one no?    We have 8 Gigabit NICs in each server...2 in each are dedicated to iScsi (stacked dedicated 6224 switches for iScsi traffic), 3 are for the VMs, 1 for cluster and one for live migration.  All recommended by Dell for this setup and software parts configured remotely by Dell.

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Moderator
Moderator

Re: PS4000 Equallogic CSV speeds

Can you private message me you name, company name, email address, EqualLogic case number and your TAM name (if known).  I would like to review the history of the issue first, and if needed, get a support engineer to discuss this with you further.

To private message me, add me to your friends list on this forum, then you will see the option to email me.

Regards,

Joe

-Joe

Social Media and Community Professional
#IWork4Dell
Get Support on Twitter - @dellcarespro

Follow me on Twitter: @joesatdell 

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