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ISCSI snapshots

Hi All,

We have new setup of FAS2020 used only for ISCSI, we have mounted 2 ISCSI LUN's on 2 ESX servers and enabled snapshots on the volume, below are teh queries:

1. How do we need to restore from ISCSI snapshots, i know its diffrent from NFS snapshots, but do we need to mount the ISCSI LUN on to a host and retrive teh data or is there any way to restore it as we do for NFS volumes.

2. I want to share a single ISCSI LUN on both ESX hosts, if i create a LUN and dont assign it to any initiator group will i be able to share the LUN with multiple ESX hosts.

3. Can we increse teh size of the ISCSI LUN on the fly, would it have any impact on the data access for the users.

Regards,

Vijay

Re: ISCSI snapshots

Vijay,

Because I like to cite my evidence as best as possible, I'm going to answer these as I can.

So, for this I will answer your first question, of how do we restore from snapshots.

Take a look at this article here, which provides you a decent amount of information in the article itself, as well as linking you off to TR3428.

VMware ESX: How to copy certain files from a snapshot without rebooting the virtual machine

Also, check out TR3428

Hopefully this helps answer and address your question (Don't hesitate to ask more questions if you need further clarification)

Thanks for the question Vijay, and pending my citeable evidence I may have responses on the other questions! Smiley Happy

Christopher

Re: ISCSI snapshots

Taking this a step further as I address the two other questions, if you reference that TR I mentioned before: NetApp and VMware Virtual Infrastructure 3 Best Practices

You will find that both of your questions are addressed in there (I highly advise reading this excellent document!)

As an example, on Page 8, it addresses iSCSI and FCP created luns as supporting resizing, but "Not in production"

With a follow-up mention on page 48 (Section 8.2 - Storage Growth Management) covering the steps to grow a VMFS Datastore

And then on page 15 (Section 4.2 - Storage Provisioning) it walks you through setting up VMware, igroups - and it goes on in additional depth as well.

Across the board I encourage you to check this Technical Document out, as it addresses not only the questions you're asking now, but likely ones you may wonder about going forward, as well as applying Best Practices and covering very important things (such as vmware vmdk alignment - Page 14, "Virtual Disk Starting Partition offsets" which often gets overlooked and when implemented up-front will allow you realize excellent benefits for your environment and future of your ESX deployment.

Look forward to more great questions and feedback from you Vijay!

Take care,

Christopher

Re: ISCSI snapshots

Hi Chris,

Thanks for the excellent doc!!

After going through the document i have implemented the following changes:

1. Creted igroups and checked access to ESX servers via LUN sharing.

2. Expanding the LUN currently configured as a VMFS datastore results in loss of teh datstore, we would need to add an extent to the datastore i norder to in expand it.

3. configured snapshots (need to test on restoring them).

4. We have two Netapp heads with both ethernet card shared, created a Portal group adding both the ethernet cardss which would support for failover of LUN in case any ethernet card goes bad.

I really appreciate your help on this, thank you SO much; will keep you posted on the results of Snaphot restore.

Regards,

Vijay

Re: ISCSI snapshots

That's great to hear Vijay!

Glad I could guide you to the information you needed!

Christopher