On Sat, Nov 19, 2005 at 12:34:27PM +0100, Bernd Zeimetz wrote: > > 1. Linux 2.6 supporting multpath i/o but why different companies > > release their own products like (powepath- from EMC.). > > afaik EMC doesn't develope powerpath for 2.6. The companies usually support > their own stuff, something that you usually won't get from them for > multipath. But afaik you'll get the support from Redhat and Novell/Suse for > their Enterprise server edition. > > > 2. What is main difference between these two? > > multipath is open source (which means it is free), the others not - you'll > have to pay money for them usually. Historically, Red Hat (and others) have not had a solution for active/passive controllers. Arrays like the EMC Clariion and HP EVA fall into this category. The mddriver only supported active/active controllers like the EMC Symmetrix. Companies like EMC and HP have not had a choice but to develop their own products. Even looking at products like Veritas DMP, active/passive wasn't an option there either. It wasn't until 4.1 that DMP supported active/passive arrays (and we'll be testing this soon). Windows had no options whatsoever. One dm-multipath stabilizes, I expect that 3rd party vendors like HP and EMC will very happily throw away their multipathing solution - it's not one of their core competencies and frankly makes them uncompetitive (a pair of HBAs and SecurePath can cost more than the server itself). I've got experience with both PowerPath (EMC) and SecurePath (HP) and both suck (in different ways at different times in their product cycles). Everybody will be much happier when products like these go away. -- Ed Wilts, RHCE Mounds View, MN, USA mailto:ewilts@xxxxxxxxxx Member #1, Red Hat Community Ambassador Program -- dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel