A storage medium used in mobile devices like digital cameras, tablets, smartphones, ...

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14
votes
4answers
6k views

Stress testing SD cards using linux

I got into a little debate with someone yesterday regarding the logic and/or veracity of my answer here, vis., that logging and maintaining fs meta-data on a decent (GB+) sized SD card could never be ...
13
votes
6answers
1k views

Is it a bad idea to use an SD card for home directory?

I'm planning to make an SD card (or a flash drive) my home directory so as to be able to work on different PCs without much hassle. Is this a bad idea for some reason?
10
votes
1answer
6k views

How can I check the condition of an SD card?

How can I check the health condition of an SD card? When I want to check a hard drive, I can use SMART, how should I check an SD card? Is there a universal approach?
8
votes
4answers
4k views

Safely use SD cards when power can go out at any time

We're working on a small embedded Linux system (2.6.35-ish) with a smallish internal NAND device for the OS and applications (250-500Meg) and an SD card with 8Gb SDHC SD cards for data. The unit's ...
7
votes
1answer
816 views

/dev/mmcblk0 partitions limit

I've just mounted a microSD card which has 17 partitions in my laptop and I'm getting the following error in the YaST partitioner: Your disk /dev/mmcblk0 contains 17 partitions. The maximum number of ...
7
votes
2answers
699 views

File system that never breaks (data loss acceptable)

There're several existing topics revolving around this issue, but what I seek is slightly different. I have an sd card on an embedded Linux and it suffers from power loss. I might be able to modify ...
7
votes
2answers
676 views

Best file system for removable media

Recently I had a SD card destroyed ( software wise ) on me. Basically as well as I can figure it out, all the metadata was wiped (ext4 card). This happened when I was working and suddenly had to write ...
6
votes
2answers
3k views

Resetting MMC controller without physically removing the card?

I'm trying to rescue data from an SDHC card using ddrescue: while true ; do ddrescue -d /dev/mmcblk0p1 mmc.img mmc.log ; done The controller, I'm not sure if it's the one on the card or the one in ...
6
votes
1answer
2k views

Eye-FI SD Card not working with inbuilt card reader

I am tring to get my cardreader to work with and eye-fi SD card. My System is as follow: #uname -a Linux computer 3.2.0-0.bpo.2-amd64 #1 SMP Thu Mar 15 20:46:44 UTC 2012 x86_64 GNU/Linux Debian ...
5
votes
1answer
71 views

card reading killing my battery, on macbook pro running Debian

I am currently using a macbook pro but the operating system is debian 8.2 not os x I am using a macbook pro but there's this one device that's just draining a lot of power. This USB device: Card ...
5
votes
1answer
526 views

Finding a unique identifier for SD cards

I have dozens of SD cards that I need to keep track of for a project. Right now, they each have a number physically written with permanent marker on the outside. This is OK, but I want to see if there ...
4
votes
2answers
3k views

Utility to TRIM unallocated space on drive

I have a drive (SD card) with a few ext4 partitions but also some unallocated space. The fstrim utility can only work within a filesystem. Before I reinvent the wheel and write one, is there another ...
4
votes
2answers
11k views

Trouble getting busybox switch_root to work

I'm working on an embedded ARM Linux system that boots using initramfs. (Here's some background from a couple earlier questions, if you're interested.) So far, thanks in part to help received here, I ...
4
votes
2answers
3k views

SD card not accessible (works in an old Nokia though)

Background I have two visually same 2GB microSD cards, both labeled "SD-C02G JAPAN", under the "2GB microSD" logo. My problem is that I can't read one of them in any device except an old Nokia 5310 ...
4
votes
1answer
25 views

Cannot reformat Micro SD Card

I need to reformat my micro SD card, however I am having some issues with it. When I go the card on my computer, it displays the following message: The folder contents could not be displayed ...
4
votes
1answer
286 views

dd, seek with one block size, write with another block size

Background Info: Copying some .bin files to an SD card (to be read by an embedded device, no filesystem) Commissioning the card requires some segments to be wiped (i.e. zero'd), and others to have ...
4
votes
1answer
12k views

Installing Ubuntu/Debian on 16 GB SD Card

Is it possible to install Ubuntu/Debian on my 16 GB SD Card ? Do I just during installation process chose my SD Card partition and install it (that doesn't work if we have USB) or do I need to install ...
4
votes
1answer
1k views

Risks involved with lazy_itable_init=1 for ext4 fs on SD card

My setup is the following: Linux kernel 2.6.28 e2fsprogs 1.42.7 64 GB class 10 SD card I am attempting to speed up the time it takes to format the entire card to an ext4 filesystem. My research ...
3
votes
2answers
2k views

dd to clone to smaller sdcard

One of my Raspberry Pi's is using a 4GB SDcard for the root/boot filesystem. As seen when mounted on another system: Disk /dev/sdc: 3904 MB, 3904897024 bytes 121 heads, 62 sectors/track, 1016 ...
3
votes
1answer
11k views

extending a partition by resize2fs

I have a 4 GB SD card. Before the image load root@ubuntu# fdisk -l Disk /dev/sdb: 3965 MB, 3965190144 bytes 49 heads, 48 sectors/track, 3292 cylinders, total 7744512 sectors Units = sectors of 1 * ...
3
votes
1answer
25 views

Wear leveling of SD card because of swap file in embedded linux

I need to enable a swap file on my embedded linux product. The problem is that the file is located on an SD card. At the moment I'm using 15MB swap and about 120MB RAM because of temporary increases ...
3
votes
1answer
82 views

Formatting an sdcard with mkfs hangs indefinitely

I am trying to format an sdcard following this guide. I am able to successfully create the partition table, but attempting to format the Linux partition with mkfs yields the following output: mke2fs ...
3
votes
2answers
259 views

Why does my SD card need authentication to access?

I'm running Ubuntu 14.04 on a Toshiba Chromebook 2 via crouton. I recently reformatted a 256GB SD card that I keep in my chromebook at all times. My problem is that every time I try to access my SD ...
3
votes
1answer
3k views

mounting a SD card without a partition

I try to mount a SDHC card under GNU/Linux. Unlike what happens usually, /var/log/syslog doesn't mention sdb1, just: Jul 26 16:07:53 xvii kernel: [ 159.404842] scsi 6:0:0:0: Direct-Access Singim ...
3
votes
1answer
127 views

Writing to exfat doesn't persist between mounts?

I... Bought a microSD card to store music on, for my Samsung Galaxy S4. Inserted it into the S4 and formatted the card (exFat). Installed fuse-exfat and exfat-utils and inserted the card into my ...
3
votes
1answer
268 views

Differences between dd in Mac OS X and Linux

When using Linux (Debian), I often use dd to copy a disk image to an SD card. I have written a script that throws an error if the device file specified in the "of" option is too large. This keeps me ...
3
votes
1answer
574 views

How can one force a re-scan of an SDIO bus from Linux user space?

On an embedded Linux platform, I have a network adapter attached to an SDIO interface. There is no Card Detect signal on this particular bus. If for instance, I turn the network adapter power on or ...
3
votes
1answer
35 views

How do I mount an external SD card without using sudo?

I wrote a bash-script with the intention to back up a specific (truecrypt-)file onto a SD-card (and a folder shared over the cloud) using the rsync command. The problem was that the SD-card usually ...
3
votes
1answer
816 views

How to make sd card as default boot in uboot?

U-Boot 2013.07 (Nov 21 2013 - 18:12:40) Memory: ECC disabled DRAM: 1 GiB MMC: zynq_sdhci: 0 SF: Detected N25Q128A with page size 64 KiB, total 16 MiB In: serial Out: serial Err: serial Net: ...
3
votes
0answers
723 views

How to check/test internal card reader speed

I got new SD card claimed to be 10 class of speed, but internal Disk utility in linux after test showed up only 6th class of speed. How can I check my card reader speed to be sure that it's not the ...
2
votes
5answers
21k views

SD card corrupt and stuck at 32MB, any way to fix it?

Using the Linux area since I'm using Linux apps and utilities. My phone crashed (several times) and managed to corrupt my microSD card. It no longer appears to have partitions and shows as 32MB ...
2
votes
1answer
538 views

What actually happens when the checksum fails for a file using btrfs?

I'm testing using btrfs on my embedded Linux system. It uses a uSD card for the rfs. This system is remotely deployed so there's no human sysadmin to take care of it. My question is what happens ...
2
votes
1answer
2k views

Realtek RTS5209 PCI-E Card Reader only work if card is inserted before boot

Hardware Info Laptop Model: Sony Vaio Pro 13 Problematic Hardware: Bulti-in Realtek Semiconductor Co., Ltd. RTS5209 PCI Express Card Reader Problem description Here is the problem, if I boot with ...
2
votes
2answers
93 views

How to mount a filesystem by 2 operating systems simultaneously?

I was wondering, is it possible to have my Raspberry Pi mount the SD that is also mounted by an digital camera? I have a scenario where I take pictures relatively fast (Raspberry Pi triggers the ...
2
votes
1answer
903 views

btrfs on SD card, what does “Btrfs detected SSD devices, enabling SSD mode” mean exactly?

I'm experimenting with using btrfs on my Debian Linux armhf system. The rfs is on a micro SD card. On bootup I get the message "Btrfs detected SSD devices, enabling SSD mode". What features does ...
2
votes
1answer
55 views

How to prepare a new MicroSDXC card for use with Android?

After buying a 64 GB MicroSDXC card and plugging it into my Android phone, it wasn't recognized. What do I need to do to use the space on this device? Many articles suggest installing closed source ...
2
votes
1answer
658 views

Chrubuntu on Acer C7: SD card reader only works on AC power?

I have an Acer C7 chromebook on which I have installed Chrubuntu. Everything works great except that the SD card reader doesn't work when the computer is running from battery power. It recognizes the ...
2
votes
1answer
104 views

How to write isolinux to an ext4 filesystem

How would I write isolinux to an ext4 filesystem on an 1 GB SD card so that it would boot at startup?
2
votes
1answer
924 views

SD card reader on Linux: SPI or SD protocol underneath

I've a notebook with a SD card reader and I was wondering if the GNU/Linux driver is using the SPI protocol or the proprietary SD protocol (one or four bits). I'm asking this because I'm testing a SPI ...
2
votes
1answer
2k views

Linux 2.6.32, busybox, Identify physical SD device

I have a USB card reader with two SD card interfaces and two USB ports (so it can also act as a USB hub) all on the same device. I am running an embedded Linux device that is unsupervised in its use ...
2
votes
1answer
5k views

Why is my SD card not being recognized?

I'm using Lubuntu 11.10 on a VAIO notebook. Here is my uname output: Linux vaio 3.0.0-16-generic-pae #28-Ubuntu SMP Fri Jan 27 19:24:01 UTC 2012 i686 i686 i386 GNU/Linux I don't know why but today ...
2
votes
0answers
51 views

SD card protected area

The Wikipedia article on SD cards mentions that about 10% of the capacity of an SD card is a so-called protected area, which is used for the security-related features of the card. Let's say I don't ...
2
votes
1answer
892 views

arch linux, x220, sd card reader

I'm running ArchLinux on a Thinkpad X220. The laptop has a built-in SD/MMC card reader. When inserting SD cards, no card is detected, nothing is logged to dmesg. The reader is listed in lshw as ...
2
votes
0answers
237 views

Installing Arch Linux on SD Card - Problem Writing Partition Table

I've been trying to install Arch Linux onto an SD card to use plugged into my macbook. Currently, I've booted into the installation media on a usb key and I'm trying to write the GPT partition table ...
2
votes
0answers
22 views

How to reload media parttion table after dd [duplicate]

When I overwrite the partition table with dd command I can't mount my new partition mmcblk0p1 because is not updated I need to force reload partition table of SD-Card mmcblk0, I unplug and plug ...
2
votes
0answers
302 views

Set PERM_WRITE_PROTECT on an SD card

From what I read here and here I gather that there is a bit on SD cards called PERM_WRITE_PROTECT that will allow me to make an SD card read only. Is it possible to set this bit from Linux? If so, ...
2
votes
1answer
623 views

sfdisk failing to write partition to disk [closed]

I am trying make my microSD card bootable to Ubuntu. I am trying to use sfdisk to create the partitions. When I do that this is the error I am getting: Using sfdisk to create partition layout ...
2
votes
0answers
800 views

USB SD card reader recognized with lsusb but no storage device shown with lsblk

I have a 2GB Micro SD card and a USB card reader. When I run lsusb I can see the card reader is recognized, but when I run lsblk I see no additional storage devices. [lane@Lane-ArchSystem 19:38:08 ...
1
vote
1answer
143 views

Disk image copied to my SD card doesn't boot

I'm following the tutorial Install Cubian to copy Cubian to my SD card. And I'm using the following command as the tutorial suggested: sudo dd if=Cubian-desktop-x1-a10-hdmi.img of=/dev/mmcblk0p1 ...
1
vote
2answers
158 views

Stress (write) Test an SD card to destruction using a simple shell script

I would like to find out how many write cycles I can get from my SD card. I have googled and found good answers like this but its too complicated for a normal person like me. Say its a 64GB exfat ...