Hi, On machine 'A' I have a pair of: Device Model: Samsung SSD 870 EVO 4TB Sector Size: 512 bytes logical/physical on top of this is an mdadm RAID-1 and that is an LVM PV. One of the LVs has been partitioned with an MBR and a single partition spanning the whole of the 400GiB LV. I took a dd of this LV and transferred it to an identically-sized LV on machine 'B' which has a pair of: Device Model: HGST HUS726T6TALN6L4 Sector Size: 4096 bytes logical/physical The LV there when examined in a partitioning tool such as "fdisk" now thinks it has a 3.2TiB partition and it is not usable. Correcting the partition sector numbers allows for use of, for example, "kpartx", to expose the partition as a loop device but the ext4 driver and fsck.ext4 remain unable to detect a superblock. I have confirmed with sha256sum that the content of the image/partition remains the same on source and destination. So, clearly the issue is the 512e sector size on source vs 4Kn on destination. Is there any way to work around this in LVM? My issue is that I would like to be able to move images of disks/filesystems around at the block level without mounting/creating filesystem and transferring with an fs-level application. If not, then possibly I can use hdparm to set the 4Kn drives to 512, which will obviously involve destroying their contents, but that is fine at this stage. I don't think the presence of a partition (as opposed to an ext4 filesystem directly upon the LV) is relevant; I think the same issues would occur with a direct filesystem. I mention it only for completeness. Also, I realise that the problems would also happen without LVM. I just wonder if there is any workaround at the LVM layer, since that is already used here. Thanks, Andy
