questions on virtual disks in ESXi (boot pool mirror and virtual disk for Apps)

[davidmueller13]

Hi, I want virtualize Truenas Scale on ESXi. For that I have some questions when I create the virtual disk(s):

Does it have any advantage adding two virtual disks for the boot pool and setting them up as a mirror (like fixing corruption)? I saw few doing this.

I know it is it is discouraged to use virtual disks or RDM for the actual data pool (For that I use a LSI-HBA). But can make a virtual disk pool just for using it for truecharts apps?

 

[artlessknave]

Please read Forum Rules. big red letters on top of forum....

Hi, I want virtualize Truenas Scale on ESXi. For that I have some questions when I create the virtual disk(s):

did you read the resource on virtualizing TrueNAS?

Does it have any advantage adding two virtual disks for the boot pool and setting them up as a mirror (like fixing corruption)? I saw few doing this.

does so is fine.

I know it is it is discouraged to use virtual disks or RDM for the actual data pool (For that I use a LSI-HBA). But can make a virtual disk pool just for using it for truecharts apps?

what is the reason for not putting them in the LSI pool?

 

[jgreco]

Does it have any advantage adding two virtual disks for the boot pool and setting them up as a mirror (like fixing corruption)? I saw few doing this.

Generally, this is acceptable. Variation on

Virtually FreeNAS ... an alternative for those seeking virtualization

[---- 2014/12/24: Note, there is another post describing how to create a full-sized FreeNAS VM directly managing a bunch of disks. THIS post is aimed at people wanting to use FreeNAS to provide a little basic file sharing off of virtual disks on shared VM storage. ----] There's been a lot of...

www.truenas.com

Do note that ESXi has been known to freak out if your datastores are not at least RAID1 protected and you try to access data on the VMDK. It can cause your VM to stall. To make it clear, the ESXi datastore is RAID1 and then you have two VMDK's which mirror each other. It seems wasteful but you don't need them to be huge.

But can make a virtual disk pool just for using it for truecharts apps?

Yes, but, same as above. Do it on RAID1 datastore or else risk issues when something bad happens causing the VMDK to hang.

 

[davidmueller13]

what is the reason for not putting them in the LSI pool?

Because the main pool is HDD based and I noticed that selecting it for apps causes drive anoise every few seconds because of writes. And i don't want to waste drive bays for a SSD only pool just for that.

 

[davidmueller13]

Do note that ESXi has been known to freak out if your datastores are not at least RAID1 protected and you try to access data on the VMDK. It can cause your VM to stall. To make it clear, the ESXi datastore is RAID1 and then you have two VMDK's which mirror each other.

Would it be enough to put the two vmdks on different datastores on different drives?

 

[jgreco]

Would it be enough to put the two vmdks on different datastores on different drives?

No. The point here is that if the hypervisor is unable to read the data from the drive, it is fairly common for the hypervisor to pop an I/O error and to pause the VM. Having two vmdk's on two different datastores does not resolve that. Having two different vmdk's on RAID1 protected storage does, however.