Check out the MD3200 (SAS, not iSCSI). It can attach 4 Hyper-V Hosts in High Availability with 6GB SAS HBA connections, no need for iSCSi switches or extra cabling. We have it working with three hosts running Citrix Xenserver and it is working beautifully. As long as you do not need distance between the storage and the servers it is a much better option. (In my opinion)
The SAS version only supports up to 4 redundantly connected physical servers when clustering (sharing the storage between multiple servers). If you're not planning to cluster, you can connect up to 8 servers.
With the iSCSI version you can connect up to 32 servers by using one or two ethernet switches.
One thing to consider is that you do have 4x1 Gig ports per controller. Also, Dell provides multipathing software that will automatically support IO over multiple NICs as long as you setup your iscsi sessions correctly.So, technically, you will be able to do 4x110 MBps. There is a also a utility that will help you setup your iSCSI sessions too (windows and linux)
You could do SAS or iSCSI
SAS is slightly faster as it has 4 6Gig SAS ports per controller but you will probably not be able to hit bandwidth limits there. In general, for SQL database type applications, you will probably be more concerned with IOPS than throughput. So, given that, iSCSI and SAS both should work fine. You might want to consider the "high performance" option that Dell sells with the MD3200 series.
Correct, the big limitation is that you can have 4 SAS hosts in a redundant connection. To me, that is enough for a MD3200 for Virtualization. The other limitation is distance, if you need your servers far away from your MD then iSCSI would work better.
From an ease of use, speed, cost, reliability perspective I see the SAS much better. (As mentioned below, SAS speeds would never be a slow down so you would not have to worry about it, while with iSCSI people are always tweaking the switches and network config to get as much throughput as possible)
Unless your SQL is some major mega financial transaction system, iSCSI even if over just one connection will be enough unless your streaming media from it.
This is your first virtualization right? I say think spindle count / iops.
Not apples to apples to your virtualized environment though as we run vmware.
We were concerned as well before virtualizing..... Here is the real rub, most of your individual I/O's are going to be very small, unless you are copying large files a lot. So the overwhelming stat will be iops and you can service a lot of freaking iops from one iSCSI connection. The sustained throughput numbers are really meaningless. Even our most demanding imaging application 100GB+ SQL DB and 40 million+ doccument image flat files where we add 20,000 more physical files each day? Never maxes out even a single connection.
The MPIO is just the gravey on an already high performing system. It does solve the large file copy issues with performance though. :)
I have a MD3200 that I'm still testing out before putting into production.
10x 600GB 15k SAS
Is it worth creating 4x Raid10 for our SBS server and 6x Raid10 for everything else? Fileserver/random VM's Or is it better to just have the 10x Raid10 for all and hope the power of the 10 spindles is better then splitting it.
Basically as it's RAID10 you'd have 2 or 3 spindles with like usage or 5 spindles which have mixed usage.
It would seam that if you have 5 spindles shared and performance is still around 3x spindles at max contention it would be better to keep all in the one lot then.
I have a query regarding PowerVault MD3200. In MD3200/MD3220 Technical Guide Book, they have mentioned it as "In the event of a power failure, the controllers are protected with battery assisted persistent cache backup which destages cache to non-volatile media for indefinite safe keeping.(page no 08)". Can anyone please explain what they mean by non-volatile media here..??
bdearlove
65 Posts
0
January 18th, 2011 10:00
Check out the MD3200 (SAS, not iSCSI). It can attach 4 Hyper-V Hosts in High Availability with 6GB SAS HBA connections, no need for iSCSi switches or extra cabling. We have it working with three hosts running Citrix Xenserver and it is working beautifully. As long as you do not need distance between the storage and the servers it is a much better option. (In my opinion)
party.marty
8 Posts
0
January 19th, 2011 01:00
hey bdearlove,
thanks for the info. do you know what features you lose out on by using SAS instead of iSCSI?
Dev Mgr
4 Operator
•
9.3K Posts
0
January 19th, 2011 06:00
The SAS version only supports up to 4 redundantly connected physical servers when clustering (sharing the storage between multiple servers). If you're not planning to cluster, you can connect up to 8 servers.
With the iSCSI version you can connect up to 32 servers by using one or two ethernet switches.
mrokkam
154 Posts
0
January 20th, 2011 11:00
Marty,
One thing to consider is that you do have 4x1 Gig ports per controller. Also, Dell provides multipathing software that will automatically support IO over multiple NICs as long as you setup your iscsi sessions correctly.So, technically, you will be able to do 4x110 MBps. There is a also a utility that will help you setup your iSCSI sessions too (windows and linux)
You could do SAS or iSCSI
SAS is slightly faster as it has 4 6Gig SAS ports per controller but you will probably not be able to hit bandwidth limits there. In general, for SQL database type applications, you will probably be more concerned with IOPS than throughput. So, given that, iSCSI and SAS both should work fine. You might want to consider the "high performance" option that Dell sells with the MD3200 series.
-Mohan
bdearlove
65 Posts
0
January 26th, 2011 04:00
Correct, the big limitation is that you can have 4 SAS hosts in a redundant connection. To me, that is enough for a MD3200 for Virtualization. The other limitation is distance, if you need your servers far away from your MD then iSCSI would work better.
From an ease of use, speed, cost, reliability perspective I see the SAS much better. (As mentioned below, SAS speeds would never be a slow down so you would not have to worry about it, while with iSCSI people are always tweaking the switches and network config to get as much throughput as possible)
JOHNADCO
2 Intern
•
847 Posts
0
January 26th, 2011 07:00
Unless your SQL is some major mega financial transaction system, iSCSI even if over just one connection will be enough unless your streaming media from it.
This is your first virtualization right? I say think spindle count / iops.
Not apples to apples to your virtualized environment though as we run vmware.
We were concerned as well before virtualizing..... Here is the real rub, most of your individual I/O's are going to be very small, unless you are copying large files a lot. So the overwhelming stat will be iops and you can service a lot of freaking iops from one iSCSI connection. The sustained throughput numbers are really meaningless. Even our most demanding imaging application 100GB+ SQL DB and 40 million+ doccument image flat files where we add 20,000 more physical files each day? Never maxes out even a single connection.
The MPIO is just the gravey on an already high performing system. It does solve the large file copy issues with performance though. :)
Pingu87
2 Posts
0
March 28th, 2011 01:00
I have a MD3200 that I'm still testing out before putting into production.
10x 600GB 15k SAS
Is it worth creating 4x Raid10 for our SBS server and 6x Raid10 for everything else? Fileserver/random VM's
Or is it better to just have the 10x Raid10 for all and hope the power of the 10 spindles is better then splitting it.
Basically as it's RAID10 you'd have 2 or 3 spindles with like usage or 5 spindles which have mixed usage.
It would seam that if you have 5 spindles shared and performance is still around 3x spindles at max contention it would be better to keep all in the one lot then.
JOHNADCO
2 Intern
•
847 Posts
0
March 28th, 2011 09:00
Hmmm.. I only have experiences with MD3000i's and on those? Spindle counts rule.
Raghuram Bhat G
14 Posts
0
June 2nd, 2011 03:00
Hi All,
I have a query regarding PowerVault MD3200. In MD3200/MD3220 Technical Guide Book, they have mentioned it as "In the event of a power failure, the controllers are protected with battery assisted persistent cache backup which destages cache to non-volatile media for indefinite safe keeping.(page no 08)". Can anyone please explain what they mean by non-volatile media here..??
Thanks in Advance :)
Regards,
Raghuram Bhat