Dell R720xD PERC H710P Integrated RAID Controller, 1GB NV Cache

[AndyLao]

Hi everyone,

I am new to the community.  If I make any mistake please forgive me.  I am under a lot of pressure from my manager to give him feedback.  Once again, if this question is already ask please forgive me.  I am very sorry.

Here is my problem. According to Vmware Virtual SAN Compatibility Guide on page 22, the Dell R720xd with Perc H710P on compatible with VSAN. According to my limited understand that VSAN requires the raid card to provide passthrough however, the raid controller, Perc H710P does not allow passthrough mode.  I understand that it will allow me to do raid 0 for each of the drives including the SSD drives.  I had bad experience with raid 0 and would like to avoid that as much as possible.  How did Vmware get it to work with VSAN without doing raid 0?

If I am unable to use the current raid controller, Perc H710p.  Which controller should I use so that I am able to use all 24 drives and is compatible with VSAN 6.5?

The only thing that I found online was the following information.  The following is the information I found online regarding Perc H710P,

https://richdowling.wordpress.com/2015/07/23/reconfiguring-vsan-storage-on-dell-perc-h710p-mini-arra...

Please help me.  I am so sorry if this question is already addressed. Thank you so much.

[rcporto]

From availability perspective there is no difference between VSAN using pass-through or RAID-0 mode, since VSAN will create copy of data in more than one host in the cluster, so if your disks or even a entire host fail, the data will be still available.

See the following blog post about some additional considerations when to choose pass-trough or RAID0 mode: Virtual SAN Hardware Guidance Part II - Storage Controllers - VMware vSphere Blog

[AndyLao]

Hello Richardson,

For Raid 0, how does the controller deals with the following scenario a 900gb fails can and I put in a 1tb drive?  Does VSAN automatically see the drive or does it requires a restart and re-image to raid 0? From my understanding, passthough would just see the new drive on VSAN. 

[rcporto]

From link I posted on my previous post:

When RAID0 mode is utilized, the the following occurs

• Virtual SAN will not manage hot-plug capabilities of drives
• Hot-plug will be managed by the storage controller software

One on the main difference between the pass-trough and the RAID0, is that with RAID0 a software layer will exist and in case a disk in RAID0 fails, you will have to manage the disk replacement from the RAID controller. But again, assuming your VSAN policy tolerate failures, no data will be lost.

[sayho]

Hello~

Unfortunately, VMware compatibility is most important (It is VMware's opinion, not me).

you can just configure raid 0 each drives.

r720xd can just use H310, H710 and H710P.

but it can't use pass-through mode.

when you using vsan RAID 0 mode, it's almost same pass-through mode.

except you must disable raid cache ... and .... when drives failure situation. you need one more step configure RAID 0.

I suggest just RAID 0 if you use r720xd.