Start by running e.g
fdisk -lu /dev/sda on each drive. The output should say something like
Code: Select all
Disk /dev/sda: 480.1 GB, 480103981056 bytes, 937703088 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 821247 409600 83 Linux
/dev/sda2 821248 937703087 468440920 83 Linux
If it says that it has physical sectors of 4096 byets then your partitions all need to start on a byte boundary that's exactly divisible by 4096. In my example there you can see sda1 starts on sector 2048 and since each sector is "512 bytes" according to the Units line, that would be on byte 2048*512=1048576 and 1048576/4096=256 which is a whole integer so the partition is aligned correctly.
This alignment check needs to be true for all the various layers in the system. So, if you use LVM then your LVs also need to be correctly aligned within the partitions that make up the PVs. If you are using LVs to attach to your VMs then they too need to start their partitions on 4096 byte boundaries.