Shared RDM VM deletion

[Deepakdpu9]

I have two VM's with RDM's ( A1 is  ON A2 is OFF). A2 VM has an RDM that's being shared by the A1 and is in service. The A2 is ready to deleted from disk but cannot be deleted as its sharing one of its RDM's. Is there a way out of this situation .

My plan :

Get downtime on A1

Remove RDM from A2 , reattach it to A1 as it own RDM.vmdk

Power ON A1

Validate it has access

Delete A2 from DISK.

Thoughts?

[rajen450m]

Hi Deepak,

You can do, they way you mentioned by just removing the RDM from A2 without selecting remove the disk files, it will remove the RDM from A2.

Regards,

[dbalcaraz]

Hi,

You don't need to power-off A1 but if you want it won't hurt you.

Just delete the Virtual Disk which has mapped the RDM but DO NOT DELETE the files.

Then, you should be able to remove A2 without problem.

If it's the same RDM you don't need to re-attach it to A1 because it's already shared (so it's the same!)

[Deepakdpu9]

dbalcaraz​ I need the RDM on A1 because A2 is being deleted and A1 still needs access to the RDM

[dbalcaraz]

Hi,

Yes, but if it's a shared RDM there is no point to attach another RDM pointer to A1 or the RDM that is attached to A2 is different?

[Deepakdpu9]

dbalcaraz​ Yes but its sharing the A2_1.vmdk and we are going to delete the A2 VM from disk after we have it attached to A1. Does that have an effect?

[rajen450m]

Hi,

If it is connected from A2 VM files folder to A1, when you delete A2 VM from the inventory and disk after removing RDM path, it may not have any affect as the disk is already connected to A1.

Regards,

[dbalcaraz]

Let's see:

A1 should have something like A1.vmdk (RDM pointer)

A2 should have A2_1.vmdk (RDM pointer)

If it's the same RDM, there is no effect on deleting the RDM pointer from A2, why?

Because it's just a pointer to the same RDM, in plain words, it's just a way to access the RDM LUN!

Now for what are you saying, if A2_1.vmdk is another RDM pointer that is not shared with A1 VM, then you just have to delete the disk (from the cross) and not delete the files. Then, go to A1 and add the RDM existing disk (A2_1.vmdk)

You don't need to power off any VM to perform the add/remove disks.

[Deepakdpu9]

dbalcaraz​ The A1 VM has a disk from A2 namely A2_1.vmdk and its running it as it is set to share from A2.

[dbalcaraz]

Hi,

A1 VM:
A2_1.vmdk

A2 VM:

A2_1.vmdk

What do you mean by set to share from A2? That it's a RDM pointer, if so, what is your doubt now?

I mean, no matter what do you want to do, but if it's only a RDM you have to delete the access from A2 and you are done.

As I said before, these are RDM and it doesn't have any downtime by deleting the RDM pointers...

[Deepakdpu9]

dbalcaraz​

My doubt is will deleting A2 fVM disk have any effect on A1 since it has A2_1.vmdk. At the moment we are unable to delete A2 VM for some reason and the only thing we think its holding it up is that A1 VM is sharing a VMDK from A2. Once we remove the RDM pointer from A2 and attach it a vmdk on A1 we think it should help us in deleting A2 from disk

[dbalcaraz · Accepted solution]

M... let's see.

I will attach an screenshot about how to do it. You don't have to attach a VMDK on A1 as it is already attached (or this is what I understand).

Let me know if the image is correct about how is configured your VMs. If it is, just follow what I wrote.

[Deepakdpu9]

dbalcaraz​

Thats a great representation and looks correct. My only concern was if deleting the A2_1 pointer and VM will effect the A1 VM in any sort, since one of its HDD is A2_1.vmdk.

[dbalcaraz]

That's why I thought that a quick/ugly representation will be better to solve the doubt!

[Deepakdpu9]

dbalcaraz​

We are going to delete the A2 VM from disk, but since the VM files of A2_1.vmdk s=exist in the A2 VM files folder. Do we need copy them over to A1 and then remove it from disk and the files from the datastore?

[dbalcaraz]

Hi,

You should move it to another folder but I suppose that when you delete the VM, as the folder contains another disk that is being used it won't delete the folder.

So, just do a Storage vMotion to place the disk in the correct VM folder (will be automatically). You can just storage vMotion to the same Datastore.