Single RAID controller, does LUNs , virtual disks groups matter?

[efasfghe]

Hi VMware Experts.

I have 5 servers (each fully loaded with 8 x 1TB local SSD disks).

I am curious :

1. If I configure raid 5 ( I will have 6 TB per host), how many LUNs / datastores should I create? Does it matter here? Anyway we still have just single raid controller, right?
2. If I am going to use VSAN , is there a difference to the answer above? One datastore per host probably is okay? Or because VSAN configuration :raid0 /passthrough better to create more LUNs/datastores?
3. Any insights about performance here?

Thanks!

[Finikiez]

Hello!

What is your local storage controller?

1. I doubt that it's possible to create several LUNs with local storage controller when you make one raid wih all disks.

2. If you make VSAN you make one shared datastore for all VSAN members.

Obviously it depends on load - how many read\writes and etc.

[efasfghe]

Thanks!

1. You are really correct! I am able to add just one LUN! So is it okay to have bigger LUN than 2TBs? 8TB , 20 TB?

2. As VSAN does not use physical raid for disks (just vsan raid) , maybe it's better to create few shared datastores? For example 1 VSAN test/staging datastore , 1 VSAN production datastore? 1 VSAN database /sql datastore etc?

[Finikiez · Accepted solution]

1. Yes, it's ok, because you have no other choice.

2. You can't make several vsan datastores. Only one vsan datastore per cluster is possible.

Doesn't matter how many ssd\hdd per host you have.

[efasfghe]

Cool! I was not aware of single datastore on VSAN!

Will see how it goes, thanks a lot!