Difference between revisions of "How to create and modify ramdisk img"
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| Line 1: | Line 1: | ||
| + | Calculate count size: | ||
| + | 1024x1500 = 1.5Gb img file | ||
| + | |||
Create 1.5GB ramdisk file: | Create 1.5GB ramdisk file: | ||
| − | dd if=/dev/zero of= | + | dd if=/dev/zero of=target.img bs=1k count=1536000 |
Clone partition table from source to target: | Clone partition table from source to target: | ||
sfdisk -d source.img | sfdisk target.img | sfdisk -d source.img | sfdisk target.img | ||
| Line 10: | Line 13: | ||
kpartx -av target.img | kpartx -av target.img | ||
DD partitions from source to target | DD partitions from source to target | ||
| − | dd bs= | + | dd bs=4M if=/dev/mapper/loop1p1 of=/dev/mapper/loop2p1 |
| − | dd bs= | + | dd bs=4M if=/dev/mapper/loop1p2 of=/dev/mapper/loop2p2 |
| − | dd bs= | + | dd bs=4M if=/dev/mapper/loop1p3 of=/dev/mapper/loop2p3 |
Mount source partition: | Mount source partition: | ||
mount /dev/mapper/loop1p4 /mnt/source | mount /dev/mapper/loop1p4 /mnt/source | ||
Latest revision as of 21:40, 21 March 2019
Calculate count size:
1024x1500 = 1.5Gb img file
Create 1.5GB ramdisk file:
dd if=/dev/zero of=target.img bs=1k count=1536000
Clone partition table from source to target:
sfdisk -d source.img | sfdisk target.img
Check partition table:
fdisk -l target.img
Automatically add partition mappings(s) from source partition table:
kpartx -av source.img
Automatically add partition mappings(s) from target partition table:
kpartx -av target.img
DD partitions from source to target
dd bs=4M if=/dev/mapper/loop1p1 of=/dev/mapper/loop2p1 dd bs=4M if=/dev/mapper/loop1p2 of=/dev/mapper/loop2p2 dd bs=4M if=/dev/mapper/loop1p3 of=/dev/mapper/loop2p3
Mount source partition:
mount /dev/mapper/loop1p4 /mnt/source
Create file system on target partition to be resized:
mkfs.ext4 /dev/mapper/loop2p4
Mount empty target partition
mount /dev/mapper/loop2p4 /mnt/target
Copy files and folders from source to target:
cp -pR /mnt/source/* /mnt/target/
Unmount source:
umount /mnt/source/
Unmount target:
umount /mnt/target/
Delete partition mappings of source:
kpartx -d source.img
Delete partition mappings of source:
kpartx -d target.img
