NetApp - cloning volumes

[zebulebu]

Guys

Bit of a long shot here I know, but has anyone here used or is familiar with NetApp SANs?

I have one at my new job and have never supported them before. We had a potential issue arise yesterday where the US support guys weren't available and I may have had to do a refresh of a development environment on my todd. It was a reasonably hair-raising moment for me - I've not yet been on any training and, other than this, they pretty much manage themselevs so haven't needed to dive in and learn how OnTap or snapshotting works. Luckily, the need for the refresh went away, so it won't be an immediate problem for the time being, but I would like to get a headstart on a few things before the issue arises again.

I understand how the technology behind them works, but the CLI reference for OnTap is a bloody nightmare to wade through, and seems to contradict itself at various points! I'm hoping that someone here will have supported them and be able to answer a couple of questions for me.

Firstly, the environment is set up as follows:

FAS270, single shelf of 13 144Gb disks with one hot spare, RAID6, single aggregate of 1.2Tb, OnTap v 7.1
Eight volumes on the aggregate - various sizes, assigned to various DB functions (data, logs, indexes)
Several LUNs, mapped via iSCSI to various disks on two servers (one dev, one production)
iSCSI Vlan presented on our core switch, using QLogic HBAs
Snapshots are created on a defined schedule (hourly for most LUNs) using SnapDrive on the two servers

The problem I face is that I need to recreate the LUNs that are referenced by the dev server so that they now reflect current live data. As far as I understand the process, it is a matter of:

Closing down the database and stopping anything that may be accessing the LUNs
Deleting all snapshots of those LUNs that need to be refreshed
Deleting the LUNs themselves
Cloning the LUNs from the live data (either by cloning the LUN itself or taking a snapshot of the live data and Bringing that up as read-writeable)
Bringing those LUNs up again by setting the iSCSI targets in our SCSI initiator software
Bringing the database up again

Now, as far as I understand it, there are different ways to go about cloning a volume - the two main ones are by 'split cloning' it - which creates a complete copy of the data (and therefore doubles the amount of data space required) or by cloning from a snapshot (which doesn't, as it just creates pointers to the data and therefore the only space necessary is that required to take snapshots of changed data)

The CLI syntax is not immediately straightforward, but I think I've worked out how to create a clone of the LUNs. However, I'm not sure I know whether or not those LUNs are immediately brought up as read-writeable - either by performing a straight "LUN Clone" command or "Clone from snapshot" command.

Anyone know?

Like I said, its a long shot, but a lot of peeps on here have exposure to a hell of a wide range of technologies and I just wondered whether anyone had used NetApps in anger before

Cheers!