Ok, so this has been fun to diagnose but I've learned a bit about LVM and brushed up on my MDADM, so overall not a bad day!
What I'm trying to accomplish is migrate 2 external enclosures with multiple 2 devices MDADM RAID1 mirros setup underneath of a giant LVM.
sda + sdb = 2TB in RAID1 with mdadm = /dev/md1 sdc + sdd = 2TB in RAID1 with mdadm = /dev/md2 VolGroup = /dev/md1 /dev/md2 Logical Volume = 100% of Available Space in VG
I have tested without mdadm and been successful with simply using the following:
umount vggroup vgchange -a n vggroup vgexport vggroup
pvscan vgimport vggroup vgchange -a n vggroup
But with the underlying mdadm I just get nothing with pvscan... Any suggestions?