Set up access to a Starwind Target as READ ONLY

[jhamm@logos-data.com]

Is there a way from the Starwind Mgmt Console to mark a LUN as read only for some hosts? We are implementing a backup server (Veeam) that will be using hardware snapshots, and want it to have only READ access to the lUNS of the virtual machines it will be backing

[Max (staff)]

Hi,
I'm not sure it's doable from the Management console.
StarWind can mount the whole device as read only, but this would apply to all initiators.
You can try setting the disk as read only on the initiator side, but I'm not sure Veeam will be able to work with it.

BTW: Is this setting a Veeam requirement ?

[anton (staff)]

Now we need to understand what you want exactly:

1) Read-write LUN (primary data) with a read-only snapshot mounted on the same target as a separate LUN (VSS way)

2) Read-only LUN on a target (reported as a read-only SCSI device)

3) Read-write LUN with a discarded writes (so after un-mount all written data would be gone rather then get submitted to disk)

So... Your choice?

[jhamm@logos-data.com]

I'll profess a little ignorance, but here it is in an nutshell:

- We have an existing Hyper-V cluster with CSV's running on StarWind

- Veeam server needs access to the CSV LUNs in order to do SAN snapshots (via Starwind VSS Provider) and offload backup processing off of the Hyper-V hosts.

- BUT, several of the whitepapers with VEEAM mention setting the LUN to read access only from the Veeam backup server to be extra careful to avoid data corruption on your HyperV CSVs.

Does that help?

Thanks,
Jeff

[anton (staff)]

Just a little bit... 1) or maybe 2). Let me talk to VEEAM Product Manager for that

[jhamm@logos-data.com]

Thanks!

Glad you have a contact over there

[anton (staff)]

OK, talked to Anton Gostev @ VEEAM and what we have:

"BUT, several of the whitepapers with VEEAM mention setting the LUN to read access only from the Veeam backup server to be extra careful to avoid data corruption on your HyperV CSVs." (c) VEEAM

I have checked and these recommendations/whitepapers are specific to VMware, and are caused by the fact that VMware uses VMFS instead of NTFS, so there is a risk of Windows turning VMFS LUN into NTFS LUN. No such risk in Hyper-V.

So... You DO NOT need to move LUN state to read-only. However we can do any of the 1), 2) and 3) no problem

[jhamm@logos-data.com]

Got it So won't need this for my environment. But if I did need something setup like #2, how would I go about that?

[anton (staff)]

Will talk about this with R&D tomorrow (Alex will proceed probably)

Got it So won't need this for my environment. But if I did need something setup like #2, how would I go about that?

[Alex (staff)]

(Updated)

Existing device can be re-added in read-only mode with the following operations:
- Remove device (files of device are kept on disk)
- Run Add device (advanced) wizard and select option "Use existing file" on "Virtual Disk Location" page.
- Select file of your device. Mark "Read-Only Mode" check-box.

Also it can be done by editing StarWInd.cfg file. Just add readonly="yes" to line of ImageFile device, and restart the service.
LUN will be marked as Read Only.
For example:
<device file="My Computer\D\img\Storage16.swdsk" name="imagefile1" readonly="yes"/>

[anton (staff)]

That's 2) way to go, right?

This functionality is not accessible from Management Console now.
It can be done by editing StarWInd.cfg file. Just add readonly="yes" to line of ImageFile device, and restart the service.
LUN will be marked as Read Only.
For example:
<device file="My Computer\D\img\Storage16.swdsk" name="imagefile1" readonly="yes"/>

We'll add this functionality to GUI wizards in a couple of weeks.

[Alex (staff)]

Yes. This setting makes LUN read only for all initiators.

[jhamm@logos-data.com]

This is not a priority for me now since VEEAM does not require it in my scenario, but what I think I was looking for is the following:

- Have the LUN be marked read/write for the Hypervisors (VMware or HyperV)

- Have the same LUN be marked read-only for Backup Servers.

Make sense?

Jeff

[Anatoly (staff)]

Actually that makes perfet sense. We`ll consider this as an option.

[KentM]

Actually that makes perfet sense. We`ll consider this as an option.

Hello,

Did this *ever* get implemented in *any* version of StarWind beginning with v8.0.9996 or later? If so, how do I go about configuring it???

Thanks,

~Kent