Storage configuration options for Windows file server VM

[J0nF]

Hi all,

I have a home setup of ESXi 3.5 running on an Adaptec 5805 with 3 x Western Digital 1TB drives in raid 5. I plan on running a number of VMs on VMFS using virtual disks ranging between 10-20GB. The bulk of the storage is for the storage volume for a windows file server VM, somewhere around the 1.5TB mark. Additional physical drives added to the Adaptec 5805 will be added to the file server storage. At least that is what I would like to achieve

My question is, what is the best option for adding the windows file server VM storage seeing as both the VMs and storage are all on the same array?

1. One big VMFS volume, add a 1.5TB virtual disk as extra storage to the VM file server and use extents when adding extra physical drives to the array

2. One 300GB partition on the array as VMFS datastore for VMs, one 1.5TB partition on the array as VMFS datastore for file server storage disk. Use extents on the 1.5TB datastore when adding extra physical drives

3. One 300GB partition on the array as VMFS datastore for VMs. Rest of array accessed via Raw Device Mapping for file server storage and extented via "normal" array expansion methods when adding extra physical drives

4. Something else as non of the above makes any sense or is technically impossible.

Many thanks for your time.

Jon

[J0nF]

Ok, after future reading it seems the largest disk file I could create on the standard 1mb block size VMFS partition is 256GB so it looks like my option 3 might be the go.

Am I on the right track here?

[J0nF]

I am currently rebuilding my arrays as per my option 3 to allow a 1.5TB array presented to a VM as a RDM. I am happy to try any options here it just takes ages on my controller to build the array so am hoping to get it setup right soon so I can start building VMs.

Surely someone must have tried this setup?

[Craig_Baltzer · Accepted solution]

Hi Jon. "Best" depends on what you want to accomplish, all 3 of your options will "work"...

1 & 2 give you the flexibility of creating VMDK files as needed and allocating space to different VMs if you need to. So for sample out of your 1.5TB you can decide that you want 500GB to go to VM1, 250 to VM2, etc., etc. Option #3 basically dedicates the 1.5TB to one VM, which ever one has the RDM mapped (the RDM will include the whole drive and aside from cluster configurations is only useable by one VM).

When you create a VMFS partition you have the option of picking the block size that fits your needs. For a 1.5TB drive you'd pick 8MB so that you could create a VMDK file as big as the entire disk if you wanted to (8MB would give you an upper limit of 2TB).

Extents will allow you to grow a single datastore by adding disk, however another approach when adding drives is to create an additional datastore, then create VMDK files and link them into the VMs as needed (you'll end up with "multiple" drives in the VM).

[rock0n]

Hi,

you can not add a local SAS "LUN" as a RDM. This was possible with "real" SCSI HBAs and pre 3.5

regards

raiko

[J0nF]

Hi Jon. "Best" depends on what you want to accomplish, all 3 of your options will "work"...

1 & 2 give you the flexibility of creating VMDK files as needed and allocating space to different VMs if you need to. So for sample out of your 1.5TB you can decide that you want 500GB to go to VM1, 250 to VM2, etc., etc. Option #3 basically dedicates the 1.5TB to one VM, which ever one has the RDM mapped (the RDM will include the whole drive and aside from cluster configurations is only useable by one VM).

This option would be fine as I was planning on using the 1.5TB as primary file storage area and as such would only need to be accessible from one VM. Seems raiko below has put that option to rest for me though ;(

When you create a VMFS partition you have the option of picking the block size that fits your needs. For a 1.5TB drive you'd pick 8MB so that you could create a VMDK file as big as the entire disk if you wanted to (8MB would give you an upper limit of 2TB).

Extents will allow you to grow a single datastore by adding disk, however another approach when adding drives is to create an additional datastore, then create VMDK files and link them into the VMs as needed (you'll end up with "multiple" drives in the VM).

Seems this is my best option to achieve what I am looking for, many thanks for your response.

[J0nF]

Hi,

you can not add a local SAS "LUN" as a RDM. This was possible with "real" SCSI HBAs and pre 3.5

regards

raiko

ah, that kind of scuppers my preferred plan then 😕 This is rather disappointing, is there no way to configure ESXi so I can add a local SAS "LUN" as a RDM?