on 16:28 Tue 08 Feb, Jason Brown (jason.brown at millbrookprinting.com) wrote: > On 02/07/2011 05:09 PM, Dr. Ed Morbius wrote: > > on 15:19 Mon 07 Feb, Ross Walker (rswwalker at gmail.com) wrote: > >> On Mon, Feb 7, 2011 at 2:36 PM, Dr. Ed Morbius <dredmorbius at gmail.com> wrote: > >>> on 13:56 Mon 07 Feb, Jason Brown (jason.brown at 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 <...> > >>> What are you using for your iSCSI target (storage array)? <...> > >>> 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? > > > > <grin> > > > > 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. <...> > >> 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). -- Dr. Ed Morbius Chief Scientist When you seek unlimited power Krell Power Systems Unlimited Go to Krell!