Storage configuration

[ManuG2k]

Hi all,

sorry for my imperfect english

I would like to create the following virtualized solution:

Two servers (ESXi host) HP DL280 G7 (2x CPU with 6 core, RAM 36 GB)
One Shared Storage with HP P2000 G3 SAS (link with the hosts are with SAS cable 6 Gb/s) HD 12 GB 15K rpm SAS 300

How do you reccomend to configure the storage P2000 ?

I thought a raid 10, with one array and one Datastore on ESXI.

I think use 11 disks in the array, with one disk configured as a spare.

Reccomended better ?

Tnx in advance!

Manuel

[biokovo]

Hi.

Maximum datastore size is 2TB, so you should create in vSphere more datastores than one.

Which RAID to use depend of I/O. If you really don't have high I/O (i.e. big databases) you can creat RAID5 or RAID6+2 which gives you more space than RAID10.

15k disks are very fast so RAID10 is maybe not what you really need.

Also, you can consider to create one volume with more datastores, or create more volumes. Each volume has isolated disks.

Regards,

Ante

[weinstein5]

Welceom to the Community - It all depends on what your VMs are going to be doing - because the disk performance is passed up to the VM but what you describe is a good general purpose setup - also keep in mund the ESXi 4 only supports volumes of 2 GB -512 B

[biokovo]

Sorry, I just see you have 300GB disks, so you can create one datastore on RAID10.

Maybe you can create RAID10 and RAID5 volumes for different purposes...

[ManuG2k]

On each host I configure 6 VM, for a total of 12 VM's.

They are almost all web servers.

2 of 12 Vm's is database server (database's is not very large but i need best I/O).

The downside of the raid 10 is to lose more space than the raid 5, but I get excellent performance, right ?

The raid 10 of 12 Disks is 1.8 Tb, but i think use 10 disks (1.5 Tb) and 2 disk for spare.

Which benefits and advantages might give me to have more of one array (or datastore) ?

[golddiggie]

How many drives does the array contain? 12GB doesn't jive... Is it a 12TB array? Still doesn't fly if there's 11 hard drives in it.

I've not used that HP storage device before, but I would configure it with RAID 10 volumes. Depending on the drive sizes, you could get enough spindles in each array for optimal performance, and not exceed the 2TB-512B VMFS limitaition (which goes away in ESXi 5). 

Conventional wisdom/best practices has been to size the LUN's for best performance, limiting how many VM's you put on each one by IOPS demands of those VM's. Such as making a high performance LUN for a SQL server, maybe not placing any other VM's on that same LUN. Then there's also having several web site VM's on a single LUN (helps if the database servers used are on another LUN, optimized for performance)...

Personally, I tend to size my LUNs to about 512GB to 1TB in size, depending on the VM's needs and such. If you want to have some VM's with larger virtual drives, consider using Raw Disk Mode there. So, make some LUNs for the VM's OS drives, and those that don't need large storage volumes, then use the rest split up for RDM volumes.

I do think this would be easier if you were using a SAN/NAS as opposed to a DAS... Then you could use either iSCSI or NFS to connect to the LUNs. With a couple of network ports in the SAN/NAS, and properly configured vSwitches, you would have good performance. I've been using a QNAP SAN/NAS in my home lab for some time now. Using both Gb NIC's in it, as well as configuring my ESXi host server iSCSI vSwitch for MPIO has made for really good performance. I wouldn't do this in a production setting, but it's really good for my home lab. I've also used the EqualLogic SAN's in production, with all four network connections (on each controller) live. Great performance there.

[ManuG2k]

HP P2000 G3 SAS have 12 drives (300 Gb SAS 15K rpm each).

[golddiggie]

With those drives in the array, I would make one RAID group of a RAID 10 configuration and then split it into either two or three volumes/virtual drives (on the RAID controller side). You could just use one RAID group and virtual drive on the array in a RAID 10 configuration, since you'll be under the ~2TB size limit. In RAID 10, without any hot spares, you should see about 1677GB worth of storage there. If the array won't let you make more than one virtual drive/LUN per disk array, then I would split it into two RAID 10 arrays and present them to the host(s) that way.

I still think you'd be better off using a SAN/NAS so that you can take advantage of HA/sVmotion/etc, but you have to work with what you've got. If possible, I would put in the request for a SAN for when budgets refresh (or funds become available). Go with a major vendor (HP, IBM, EqualLogic, Compellant, even EMC) so that you know you'll have something that will work well. Especially if this is in a work environment. For a home lab, it's not as important and you can get away with lower tier hardware.

[biokovo]

This is shared SAS storage, so HA, vMotion ... works ok, like on FC or iSCSI.

Performance are great, 6 Gb per port.

Regards

[Degies]

Hi

I am browsing through the posts and came accross this post. My Question is with regards to the Shared storage and HA and Failover on SAS specific

I am looking to procure a HP p2000 with two DL380 G8 servers. The P2000 and SAS controllers are on the HCL. I need to understand how I can present the LUN's to the two servers for HA. I have done this on ISCSI many times, but SAS is new to me.

I am looking for a guide to a bit of a How to. I do understand that on SAS you cannot present the same lun to two different hosts at the same time so how would you configure failover ?

My thread " http://communities.vmware.com/thread/398484

[biokovo]

Hi.

Like I said, this is a shared storage and you CAN present one volume on two or more servers.

P2000 come with one or two controllers, every with 4 ports, so you can connect directly servers on the same LUN and you don't need SAS switch.

If you have two controllers and two ports server SAS card, you have redundancy.

I implement exactly the same enviroment a few months ago and believe me, it works great.

Regard