If I am reading what I can find correctly - -alloc=anywhere defeats the mirror code from attempting to put on 2 different physical devices. The man pages seem to lack info on what other values there are for that but disables device mirroring. On Sat, Feb 22, 2014 at 1:14 AM, Julie Ashworth <ashworth@berkeley.edu> wrote: > hi all, > > just some background... > I installed a CentOS5 server in 2010 with a mdadm RAID1 containing 2 partitions (/dev/sda1 and /dev/sdb1). /dev/sda1 failed, and unfortuately, the mirror failed to sync with a new drive. > > On this RAID1, I have one VG (VolGroup00) with 5 LVs. > > I contacted the folks on the mdadm mailing list. The data on /dev/sdb is good, so they recommended that I convert the linear LVs to mirrors (to copy the data to a new drive). > > I formatted a new drive (/dev/sde) identical to /dev/sd[ab], added it to a mdadm device (/dev/md2), which I then added to my VG: > mdadm --create --level=1 -n 2 /dev/md2 /dev/sde2 missing > pvcreate /dev/md2 > vgextend VolGroup00 /dev/md2 > > I then converted all my volumes to mirrors: > lvconvert -m1 --mirrorlog=mirrored --alloc=anywhere /dev/VolGroup00/srvlv > lvconvert -m1 --mirrorlog=mirrored --alloc=anywhere /dev/VolGroup00/rootlv > lvconvert -m1 --mirrorlog=mirrored --alloc=anywhere /dev/VolGroup00/swaplv > lvconvert -m1 --mirrorlog=mirrored --alloc=anywhere /dev/VolGroup00/varlv > lvconvert -m1 --mirrorlog=mirrored --alloc=anywhere /dev/VolGroup00/tmplv > > (in case you're wondering, when this completed, I added /dev/sda1 to /dev/md2, so /dev/md2 is a fuctional mdadm RAID1). > > Now... the problem ;).... > > When I run 'lvs' I see that the LV mirror extents were created on the same device (/dev/md1): > > # lvs -a -o +devices > LV VG Attr LSize Origin Snap% Move Log Copy% Convert Devices > rootlv VolGroup00 mwi-ao 10.00G rootlv_mlog 100.00 rootlv_mimage_0(0),rootlv_mimage_1(0) > [rootlv_mimage_0] VolGroup00 iwi-ao 10.00G /dev/md1(0) > [rootlv_mimage_1] VolGroup00 iwi-ao 10.00G /dev/md1(4036) > [rootlv_mlog] VolGroup00 mwa-ao 32.00M 100.00 rootlv_mlog_mimage_0(0),rootlv_mlog_mimage_1(0) > [rootlv_mlog_mimage_0] VolGroup00 iwi-ao 32.00M /dev/md2(4) > [rootlv_mlog_mimage_1] VolGroup00 iwi-ao 32.00M /dev/md1(4356) > > > My long-term goal is to convert the mirror back to a linear volume using just /dev/md2, i.e. > lvconvert -m0 /dev/VolGroup00/rootlv /dev/md1 > lvconvert -m0 /dev/VolGroup00/swaplv /dev/md1 > lvconvert -m0 /dev/VolGroup00/srvlv /dev/md1 > lvconvert -m0 /dev/VolGroup00/varlv /dev/md1 > lvconvert -m0 /dev/VolGroup00/tmplv /dev/md1 > > ... so it seems problematic that both extents are on /dev/md1. > > I thought lvm was supposed to use both physical devices. Do you know why both extents were created on the same physical device? > Should I create another extent on /dev/md2 before I remove the /dev/md1 extent(s)? If so, can you give me an example of how to use lvconvert in this case? > > Thanks in advance! > best, > Julie > > > _______________________________________________ > 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/ _______________________________________________ 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/
