On Sat, 14 Apr 2018 00:00:15 +0200 Martin Wilck <mwilck@xxxxxxxx> wrote: > When the first path to a device appears, we don't know if more paths > are going to follow. find_multipath "smart" logic attempts to solve > this dilemma by waiting for additional paths for a configurable time > before giving up and releasing single paths to upper layers. > > These rules apply only if both find_multipaths is set to "smart" in > multipath.conf. In this mode, multipath -u sets > DM_MULTIPATH_DEVICE_PATH=2 if there's no clear evidence wheteher a > given device should be a multipath member (not blacklisted, not > listed as "failed", not in WWIDs file, not member of an existing map, > only one path seen yet). In this case, "multipath -u" also sets the > variable FIND_MULTIPATHS_WAIT_UNIL to a relative time stamp (we need > to use relative "monotonic" time stamps because this may be triggered > early during boot, before system "calendar" time is correctly > initialized). > > In the DM_MULTIPATH_DEVICE_PATH=2 case, pretend that the path is > multipath member, disallow further processing by systemd (allowing > multipathd some time to grab the path), and set a systemd timer to > check again after the given timeout. If the path is still not > multipathed by then, pass it on to systemd for further processing. > > Signed-off-by: Martin Wilck <mwilck@xxxxxxxx> > Reviewed-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx> > --- > multipath/multipath.rules | 61 > ++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 58 > insertions(+), 3 deletions(-) > Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Cheers, Hannes -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
