Stuart D. Gathman wrote on Tue, 9 Dec 2008 13:38:46 -0500 (EST): > 1) create md2 from sda3 and sdb3 > 2) pvcreate md2 > 3) add sda3 to VG - LVM complains about dup and uses sdb3 instead A bit different. But thanks for this hint. I checked my bash history now. Short summary: mdadm --create --verbose /dev/md3 --level=1 --raid-devices=2 /dev/sda3 missing mdadm --detail /dev/md3 pvcreate /dev/md3 pvcreate /dev/md3 -ff vgcreate dom1 /dev/md3 (to avoid name clash with dom0 on sdb3) .. some lvcreate and other stuff mdadm --detail /dev/md3 reboot vgchange dom1 -an vgrename dom1 dom0 vgchange dom0 -ay mdadm /dev/md3 -a /dev/sdb3 reboot So, I did it all alright. I was wrong with my assumption about using the wrong device for the PV. However, I only notice now that /dev/md3 is gone for good, mdadm cannot find it. I had not been paying attention and thought that md2 was the array in question. (Thinking md0=sda1/sdb1, md1=sda2/sdb2, md2=sda3/sdb3, but I used md0=sda1/sdb1, md2=sda2/sdb2, md3=sda3/sdb3). So I didn't notice it. Going further back in the history, it seems I forgot to pvremove the earlier existing PV /dev/sda3 (which had the same structure and data) before creating the PV on /dev/md3. That's why I had to -ff /dev/md3 I assume. It seems that after adding sdb3 to the array and rebooting the array dissolved completely and the existing PVs on sda3 and sdb3 came back into existence. And I thought it was an effect of the mirror sync. So, I think I will just start over by removing /dev/sda3 now completely, recreating the raid array and then recreating the PV on it. I think I should then be able to pvmove the LVs from /dev/sdb3 to /dev/md3, right? Problem solved. This time. However, as this is the second time that this or a similar array just vanishes I wonder if there's something else going on. e.g. some kind of unwanted interaction between LVM and mdraid partitions. The other two raid arrays on the disk are absolutely stable and don't use LVM. Kai -- Kai Schätzl, Berlin, Germany Get your web at Conactive Internet Services: http://www.conactive.co _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
