on 16:28 Tue 08 Feb, Jason Brown (jason.brown@millbrookprinting.com) wrote:
On 02/07/2011 05:09 PM, Dr. Ed Morbius wrote:
on 15:19 Mon 07 Feb, Ross Walker (rswwalker@gmail.com) wrote:
On Mon, Feb 7, 2011 at 2:36 PM, Dr. Ed Morbius dredmorbius@gmail.com wrote:
on 13:56 Mon 07 Feb, Jason Brown (jason.brown@millbrookprinting.com) wrote:
I am currently going through the process of installing/configuring an iSCSI target and cannot find a good write up on how to prepare the disks
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What are you using for your iSCSI target (storage array)?
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Truth is, there's a lot of flexibility with iSCSI, but not a lot of guidance as to best practices that I could find. Vendor docs have tended to be very poor. Above is my recommendation, and should generally work. Alternate configurations are almost certainly possible, and may be preferable.
If a best practices doc could be handed to you right now, what would you like it to contain?
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I've got about 35 pages of that document sitting on my local HD now. Negotiating with management about releasing some of it in some form or another.
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I would be happy to draft something up and put it on a wiki somewhere, but I would need a list of talking points to start with.
How's this do you?
In our configuration, we are going to have our iSCSI targets and initiators all connected to the same layer 3 switch and isolate the iSCSI traffic on separate networks. Would it be beneficial to also set up multipath for this as well?
That's pushing the limits of my knowledge/understanding.
Multipath aggregates multiple pathways to a data store. In the case of the Dell equipment mentioned in my post, there are two controllers, with 4 TOE/NIC cards each, offering 8 pathways to each target storage LUN.
Multipath aggregates all 8 pathways to a single target, and provides both performance and availability enhancements by utilizing these pathways in turn (defaulting to round-robin sequencing), and presumably disabling use of any pathway(s) which become unavailable (whether or not any monitoring/alerting of this failover/fail-out is possible would be very useful to know).
It's also possible to configure multiple initiator pathways, though in our case we've already aggregated multiple NICs into a bonded ethernet device.
From the description you've provided, I don't think you've got a multipath configuration. I don't know what would happen if you attempted to set up multipath, but presuming not too much magic smoke escapes, I'd be interested in finding out.
Presumably you'd have to configure /etc/multipath.conf appropriately to pick up the target(s).