Selon Lars Marowsky-Bree <lmb@xxxxxxx>: > On 2004-11-08T14:10:10, christophe.varoqui@xxxxxxx wrote: > > > > Christophe, any particular wishes on how to implement this in the > > > multipath-tools? Would you want an additional helper to call to > > > answer the question of which PG should be active or bypassed first? > > > > > I guess you lost me one more time, as I thought the response to this > > particular question was under userspace responsability. > > > > Yes, that's why I asked how you'd want to implement it in the > multipath-tools. /sbin/multipath must find out somehow which PG to > activate first, right? > Right : it already does. The logic is based on the priority framework. You can plug-in path-prioritizer callouts. Default path prio is 1 for a valid path, 0 for a failing path. So by default the pg with most active paths wins. I also took a pick at a prioritizer that brings into the equation the number of LU in control of a controler, so that it can balance the LU across all controlers available. I guess you can alter the pg priorities the way anyone can imagine based on that framework. With the current kernel driver, PG are fed in params strings in top-down summed-path-priority order. Feeding those priority numbers directly into the params strings and keep the PG statically ordered shouldn't be too invasive a change. regards, cvaroqui