Difference between revisions of "Format SSD MMC"

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(camera)
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* '''mkfs.vfat''' - create filesystem
 
* '''mkfs.vfat''' - create filesystem
 
* '''dd''' - clean filesystem from the partition for '''fast recording'''
 
* '''dd''' - clean filesystem from the partition for '''fast recording'''
 +
 +
  
 
==<font color="blue">SSD or USB</font>==
 
==<font color="blue">SSD or USB</font>==
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** Do not make a file system on the partition
 
** Do not make a file system on the partition
  
===PC===
+
===pc===
 
The same as above
 
The same as above
 +
 +
  
 
==<font color="blue">MMC</font>==
 
==<font color="blue">MMC</font>==
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mkfs.ext4 /dev/mmcblk0pX
 
mkfs.ext4 /dev/mmcblk0pX
  
===PC===
+
===pc===
 
* Same as above except the MMC might be detected as /dev/sdX
 
* Same as above except the MMC might be detected as /dev/sdX
 
* If MMC is for boot the partition table type must be '''msdos''', not gpt
 
* If MMC is for boot the partition table type must be '''msdos''', not gpt
 +
 +
  
 
==<font color="blue">'Erase' a file system from a partition</font>==
 
==<font color="blue">'Erase' a file system from a partition</font>==
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* To erase the drive's partition table (better use '''fdisk'''):
 
* To erase the drive's partition table (better use '''fdisk'''):
 
  $ dd if=/dev/zero of=/dev/sda bs=512 count=2
 
  $ dd if=/dev/zero of=/dev/sda bs=512 count=2
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 +
  
 
==<font color="blue">Useful links</font>==
 
==<font color="blue">Useful links</font>==

Revision as of 12:56, 29 December 2016

About

Help tips for formatting:

  • SSD (internal or external)
  • MMC (&muSD card - normal or recovery)
  • USB drive

Can be done either from the camera or PC, the required programs are:

  • fdisk - format into partitions
  • mkfs.ext4 - create filesystem
  • mkfs.vfat - create filesystem
  • dd - clean filesystem from the partition for fast recording


SSD or USB

camera

  • Find out the device name:
$ dmesg
  • Check if it is already partitioned:
$ cat /proc/partitions
  • manage partitions:
$ fdisk /dev/sda
  • format a partition for file storage:
$ mkfs.ext4 /dev/sda1
  • for fast recording
    • Do not make a file system on the partition

pc

The same as above


MMC

camera

Make sure the camera is not boot from the MMC - in MMC boot by default the camera gets the boot files from /dev/mmcblk0p1 (FAT32) and mounts /dev/mmcblk0p2 (EXT4) as /.

  • check boot mode:
$ mount | grep " / "
  • check existing paritions:
$ cat /proc/partitions
  • manage partitions:
$ fdisk /dev/mmcblk0
  • format a partition for file storage:

mkfs.ext4 /dev/mmcblk0pX

pc

  • Same as above except the MMC might be detected as /dev/sdX
  • If MMC is for boot the partition table type must be msdos, not gpt


'Erase' a file system from a partition

Sometimes there is a need to this:

  • if the drive was partitioned several times and the old file system journal starts from a location of a new partition - the file system will surely show up.
  • by accident

Examples:

  • Use dd:
    • 'Erase' a filesystem from /dev/sda1
$ dd if=/dev/zero of=/dev/sda bs=1MB count=1 seek=1
  • 'Erase' a filesystem on /dev/sda2, if /dev/sda1 size is SIZE MB:
$ dd if=/dev/zero of=/dev/sda bs=1MB count=1 seek=SIZE
  • To erase the drive's partition table (better use fdisk):
$ dd if=/dev/zero of=/dev/sda bs=512 count=2


Useful links

  • github:elphel-tools-update - write_bootable_mmc.py
    • the script is used to create a bootable MMC from a PC (the camera doesn't have parted and kpartx installed)
    • it has examples of using dd, parted, mkfs, kpartx
  • MMC boot
    • prepare a bootable μSD card and boot