dracut doesn't see my partitions

[urgrue]

Hi,

dracut fails to find my root vg (/dev/sda2).
Dropping to rdshell, I can see that /dev/mapper only contains sda - but
no partitions. No wonder LVM cant find the PV. debug output shows that
it scanned sda but determined it had partitions, but never gets to the
partitions themselves.

At rdshell I can simply:
kpartx -a /dev/sda (my partitions appear)
lvm vgscan ; lvm vgchange -ay rootvg
exit
and happily bootup continues and all seems well.
But reboot repeats the situation. How can I fix this permanently? I've
tried running dracut with every option I can think of but to no avail.
It always boots and only sees sda, not sda2 or other other partitions.

This all began because somehow rhel6 set up multipathing on my internal
drive (/dev/sda = /dev/mapper/mpatha) and I was trying to get rid of
that (blacklist sda in multipath.conf).

If I un-blacklist sda it boots again, but rootvg is back to
/dev/mapper/mpatha2.

Any ideas?