Dne 25.8.2013 13:28, oliver_block2@web.de napsal(a):
Dear LVM list, this is my first posting to this list and actually I am making my first experiences with LVM. The following is my situation: I had a RAID 1 consisting of /dev/sdb1 and /dev/sdc1 making /dev/md2 and used this device as a physical volume for LVM. I used this inside the volume group vg_data. Now I decided to convert this RAID 1 into a RAID 5 by "adding a third and identical partition /dev/sdd1". It follows how I am going to realize this: First I removed /dev/sdc1 from /dev/md2 (the old RAID 1) leaving it in degraded state. Then I created a new RAID 5, having device name /dev/md0 with a total of three disks, but running only with two disks for the moment, namely /dev/sdc1 and /dev/sdd1. The plan is now to initialize /dev/md0 as a physical volume and add a volume group and logical volume on top of this. Then I would copy the data from the old RAID 1 to the new RAID 5. Finally I will remove the old RAID 1 and add the remaining device /dev/sdb1 to the new RAID 5. Then the conversion would be complete. Now the actual problem related to LVM:
You need to make sure you have proper filter rules set in lvm.conf.
While trying to initialize the new /dev/md0 as a pysical volume for LVM, I get the following message: # pvcreate /dev/md0 Incorrect metadata area header checksum on /dev/md0 at offset 3000456183808 Found duplicate PV LNqPKpqdtqcLkmiqHYOeeVddNYx7FDOq: using /dev/md2 not /dev/md0 Can't initialize physical volume "/dev/md0" of volume group "vg_data" without -ff
When you are destroying previous raids - you should properly wipe disk headers. Otherwise you need to use force options to overwrite existing one, with the risk you could do more damage if you are not 100% what you are doing.
Zdenek _______________________________________________ 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/
