Chandra Seetharaman wrote: > On Thu, 2007-06-21 at 20:13 +0200, Markus wrote: >> Hi, >> >> i do have an active-passive Storage where the LUN could be used by >> both Controllers but one is bloody slow. I tried all >> /sbin/mpath_prio_* ways do determin which is the "active" one but none >> of them worked. Is there a way to set this manually? Is there a >> different way to determin which is which rather than using the >> existing Commands? > > If your device is not one of the supported devices, you can ask the > vendor about how to determine the active and passive paths. > > mpath_prio_tpc is a good example of how the active/passive device > information is used to determine the path priority. > Yes, but this assumes that documentation about the device is available. That is not always the case (no NDA, uncooperative Vendors, or Vendor gone out of Business etc.) There is actually an easier way to do this: As all the mpath_* callouts are in fact standalone programs, so you can easily supply your own callout. Just write a small shell script which takes the device name as input. The priority is just the return value of that program; the path with the highest priority will take precedence over all the others. Paths with identical priorities will be grouped into a path group if the policy is set to 'group_by_prio' (which I would recommend if a priority callout is specified). The task of figuring out the physical location of a controller by specifiying the device node is left to the reader. But relying on udev here might be dangerous as multipathd might run in parallel to udev. HTH. Just out of curiousity: Which machine is that? Would be an idea to put that into the hardware table, if only with a large fat "Don't use that array unless you know what you're doing" kinda-thing warning. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Markus Rex, HRB 16746 (AG Nürnberg) -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
