dd to backup mbr
usually we use dd to backup MBR, but few people knows that you may destroy your Partion table if not used correctly. So I'd write this to notify you.
MBR Total size
446 + 64 + 2 = 512 byte
446 bytes is Bootstrap, this is what we manly backup
64 bytes is Partion table
2 bytes is Signature
if you restore the MBR to a different disk, like backup sda, but restore to sdb, then the 64 + 2 shouldn't be used
So we come up with these commonds:
backup:
# dd if=/dev/sda of=mbrsda.bak bs=512 count=1
restore all, including Partion table
# dd if=mbrsda.bak of=/dev/sdb bs=512 count=1
only for Bootstrap, Partion table is not destroyed
# dd if=mbrsda.bak of=/dev/sdb bs=446 count=1
评论