Selon Lars Marowsky-Bree <lmb@xxxxxxx>: > > Hi, I'm kind of unsure. What does multipath-tools now mean for LVM2 and > EVMS2's multipath support, given a distributors perspective? ;-) > > Do the multipath tools handle all multipath scenarios we may encounter > (or at least are supposed to), and will LVM2 and EVMS2 stack cleanly on > top of it? > the multipath-tools design is policy agnostic : the multipath configuration tool has 2 sets of policies : * paths grouping policies (drive the number and content of priority groups) : * one priority group (full IO spreading) * one priority group per path (failover, only one path active at a time) * one priority group by serial number (spread IO to all paths through a controler in a pair) * one group for active paths, one group for failed paths (for controlers that disable their fallback paths) * UUID fetching policies (methods to get the UUID that will be used to coalesce paths into multipaths) * SCSI INQ EVPD page 0x83 : LU WWID the multipathd daemon has only one set of policies : methods to determine if a path is up or down. * do a SCSI TUR * do a test IO policies can be added to fit every needs. policies are selected based on the SCSI strings tuple (vendor/product) hope it helps, cvaroqui