Format SSD MMC: Difference between revisions

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==<font color="blue">SSD or USB</font>==
==<font color="blue">SSD or USB</font>==
===from camera===
===camera===
* check the SSD is already partitioned:
* check the SSD is already partitioned:
  $ cat /proc/partitions
  $ cat /proc/partitions
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* for '''fast recording'''
* for '''fast recording'''
** Do not make a file system on the partition
** Do not make a file system on the partition
===PC===
The same as above


==<font color="blue">MMC</font>==
==<font color="blue">MMC</font>==
 
===camera===
If done from the camera make sure it is not boot from the MMC - in MMC boot by default the camera gets the boot files from /dev/mmcblk0p1 (FAT32) and
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 /.
mounts /dev/mmcblk0p2 (EXT4) as /.
* check boot mode:
* check boot mode:
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* manage partitions:
* manage partitions:
  $ fdisk /dev/mmcblk0
  $ fdisk /dev/mmcblk0
* mkfs
* 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


==<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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** the script is used to create a bootable MMC from a PC (the camera doesn't have ''parted'' and ''kpartx'' installed)
** 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'''
** it has examples of using '''dd''', '''parted''', '''mkfs''', '''kpartx'''
* [[Sd_boot_rootfs MMC boot]] - prepare a bootable &mu;SD card and boot


[[Category:393]]
[[Category:393]]

Revision as of 19:52, 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

  • check the SSD 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
  • Sd_boot_rootfs MMC boot - prepare a bootable μSD card and boot