Confused about partitions on SD Card

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1

I was looking to resize the partition on my little SD card so I could use the whole thing. I'm following the instructions here:

  http://elinux.org/Beagleboard:Expanding_File_System_Partition_On_A_microSD

According to mount, my rootfs is:

/dev/mmcblk0p1 on / type ext4 (rw,noatime,errors=remount-ro,data=ordered)

But if I check the partition map with fdisk:

# fdisk /dev/mmcblk0

Command (m for help): p

Disk /dev/mmcblk0: 3980 MB, 3980394496 bytes
114 heads, 26 sectors/track, 2622 cylinders, total 7774208 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

        Device Boot Start End Blocks Id System
/dev/mmcblk0p1 * 2048 3461119 1729536 83 Linux

I only see one rather small partition. If I look at the other device (which I presume is the eMMC):

# fdisk /dev/mmcblk1

Command (m for help): p

Disk /dev/mmcblk1: 3925 MB, 3925868544 bytes
4 heads, 16 sectors/track, 119808 cylinders, total 7667712 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

        Device Boot Start End Blocks Id System
/dev/mmcblk1p1 * 2048 198655 98304 e W95 FAT16 (LBA)
/dev/mmcblk1p2 198656 7667711 3734528 83 Linux

I see what I expect to see according to the instructions.

But I'm not sure I'm looking at the right partition map/device.

Which one is the SD card?

Thanks,

2

http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#Expanding_File_System_Partition_On_A_microSD

Regards,

3

Oh, that's much better! I'd update the other page, but I don't seem to be able to edit it.

4

This happened:

debian@beaglebone:/opt/scripts/tools$ sudo ./grow_partition.sh
Media: [/dev/mmcblk0]

Disk /dev/mmcblk0: 121472 cylinders, 4 heads, 16 sectors/track
Old situation:
Warning: The partition table looks like it was made
  for C/H/S=*/114/26 (instead of 121472/4/16).
For this listing I'll assume that geometry.
Units = mebibytes of 1048576 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start End MiB #blocks Id System
/dev/mmcblk0p1 * 1 1689 1689 1729536 83 Linux
    start: (c,h,s) expected (0,78,21) found (0,32,33)
    end: (c,h,s) expected (1023,113,26) found (215,113,26)
/dev/mmcblk0p2 0 - 0 0 0 Empty
/dev/mmcblk0p3 0 - 0 0 0 Empty
/dev/mmcblk0p4 0 - 0 0 0 Empty
New situation:
Units = mebibytes of 1048576 bytes, blocks of 1024 bytes, counting from 0

   Device Boot Start End MiB #blocks Id System
/dev/mmcblk0p1 * 1 3795 3795 3886080 83 Linux
/dev/mmcblk0p2 0 - 0 0 0 Empty
/dev/mmcblk0p3 0 - 0 0 0 Empty
/dev/mmcblk0p4 0 - 0 0 0 Empty
Successfully wrote the new partition table

Re-reading the partition table ...
BLKRRPART: Device or resource busy
The command to re-read the partition table failed.
Run partprobe(8), kpartx(8) or reboot your system now,
before using mkfs
If you created or changed a DOS partition, /dev/foo7, say, then use dd(1)
to zero the first 512 bytes: dd if=/dev/zero of=/dev/foo7 bs=512 count=1
(See fdisk(8).)
debian@beaglebone:/opt/scripts/tools$

5

Meant to add: but it seems to have worked.