4 votes
Accepted

How NOOBS OS boots? (in recovery mode)

This is what I have found out after I checked out noobs code as well as reverse engineering it. For booting recovery.efi is loaded by bootloader. From here kernel is loaded from recovery.img or some ...
Abhiram Shibu's user avatar
4 votes
Accepted

Disable Single User Mode

Put the data you're trying to protect on a separate partition and encrypt it. Typical users will want to encrypt /home. You could also encrypt the root partition itself, though that will be more ...
Dmitry Grigoryev's user avatar
4 votes

Corrupted SD Card - how to fix, or recover data?

Start by making an image of your SD card (e.g. dd if=/dev/mmcblk0 of=backup.img bs=4M). Trying to fix existing filesystem errors on a failing SD card will produce new errors in relocated sectors, and ...
Dmitry Grigoryev's user avatar
3 votes
Accepted

Recover an ext4 due to the super block flag

In general, this is an indication of a dying sd card. What happens is, that fsck tries to recover the journal, tries to write the superblock, but then finds that the superblock is not updated. If you ...
Ljm Dullaart's user avatar
  • 2,481
3 votes
Accepted

how to recover removed directories

You are crying over spilled milk. rm is generally irreversible, and unless you had the Gold Codes stored on yor SD card, it's really not worth the effort. So yes - re-flash your SD card, and start ...
Seamus's user avatar
  • 21.8k
2 votes

Reverting Display Brightness Changes

You could simply insert the SD card back in your RPi and try to get a signal over SSH or normal HDMI. After that you can activate the backlight with echo 0 > /sys/class/backlight/rpi_backlight/...
Paul's user avatar
  • 86
2 votes

Restore deleted files on Raspbian Jessie

Give TestDisk a try. BUT from another computer. As you have no Windows at hand, this runs under Linux. Good luck.
Hendrik Eggers's user avatar
2 votes

Is possible to make the backup and the recovery root partition from one to the other?

Be very careful when using the dd command because a mistake of one character can destroy the wrong partition! Your dd command above has blanked (insert similar catastrophic word - destroyed, zeroed, ...
John Hawthorne's user avatar
2 votes
Accepted

rPi4 no longer capable of HDMI output. Eeprom recovery did not help

The question has a solution. in the comments it is noted, that the HDMI cable was broken. Replacing it with a new one solved the problem.
Ingo's user avatar
  • 42k
2 votes

Pi 3b+ boot problem

It seems your SD Card has reached end of live. If so it will not help much do any (new) installations on it again. You should use a new SD Card and do as less as possible working with the old SD Card, ...
Ingo's user avatar
  • 42k
2 votes

How to enter Recovery Mode without USB keyboard?

You can use forcetrigger. From the NOOBS readme: If you are unable to use either the GPIO or keyboard to trigger entering Recovery Mode, you can: Append forcetrigger to the argument list ...
Mario Olivio Flores's user avatar
2 votes

how to recover removed directories

EXT4 is a very complex filesystem for which there is no common undelete algorithm. Recovery tools are typically only able to restore individual files, often without original file names or paths. If ...
Dmitry Grigoryev's user avatar
2 votes

Is it possible to select the root partition at boot time using GPIO pins

This answer does not address directly your question but it may solve your problem. After reading all suggested solutions it seems not to be simple task to have a save second boot option. A broken ...
Ingo's user avatar
  • 42k
1 vote

Raspberry Pi not booting "recover4.elf is not compatible"

The short answer is: download the latest version for the OS instead of cloning existing SD cards. The longer answer: Read the last two lines in the output. It says: This board requires newer software ...
Ljm Dullaart's user avatar
  • 2,481
1 vote

Is it possible to select the root partition at boot time using GPIO pins

The odds of having a "bricked" system will be a product of the probability of a critical problem (P1) and the probability of the recovery mechanism not working as planned (P2). Designing a ...
Dmitry Grigoryev's user avatar
1 vote

how to recover removed directories

Presuming that your root filesystem is ext4... There are undelete tools you can use, but you must have turned off your machine immediately after discovering that the files had been deleted. Linux is ...
JohnGH's user avatar
  • 111
1 vote

Disable Single User Mode

This is IMPOSSIBLE. If others have physical access to the system there is nothing you can do to prevent access. This pretty much applies to all computer systems. The access (more commonly referred to ...
Milliways's user avatar
  • 59.6k
1 vote

How NOOBS OS boots? (in recovery mode)

You are unlikely to get a definitive answer because none of us use NOOBS. (Those who want multi OS use PINN .) NOOBS is actually an Operating System installer and boot manager. You CAN NOT "boot ...
Milliways's user avatar
  • 59.6k
1 vote

how to remove recovery mode screen in Raspberry pi 3 b+

Rewrite your SDCard with RaspiOS32 rather than NOOBS. NOOBS is past its use-by date. Get the Raspberry Pi Imager (aka RPImager) from https://raspberrypi.org/downloads to reformat, download RaspiOS and ...
Dougie's user avatar
  • 5,271
1 vote

Accidently disabled overscan on pi 4b

With the information supplied it is difficult to suggest any answer. If you "don't want to lose any files and documents" DO NOTHING with the SD Card. Do a fresh installation - preferably Raspbian NOT ...
Milliways's user avatar
  • 59.6k
1 vote

I tried to hard wire power to pi 3 b, and smoked the board... File recovery?

All files are stored on the SD card. There is no other non-volatile storage on the Pi. Extracting the files from the SD card is tricky without booting from the SD card, so just pop it into another Pi, ...
Heath Raftery's user avatar
1 vote

Recovery of SRM save game file from Retropie corrupt SD card

We should try to do typical disaster recovery. This isn't an easy task but I started this answer with suggestions that I think it is best to start with. With your comments we will improve the answer ...
Ingo's user avatar
  • 42k
1 vote

Hi, I have falshed o/s for my rasberry pizero W on my 32gb sd card which contained my lots of data,So all I want to ask can I recover it back?

When you flash an sdcard any existing data is overwritten and gone for ever. Most flashing programs warn you of this before writing
Bra1n's user avatar
  • 1,251
1 vote

Recover files from RPi after doing chmod 777 / -R?

Oh Man, what a screw up.Do you have any other access to the device? In all honesty I would mount drive on another computer, copy important files and reinstall. Unfortunately Many things in linux ...
crasic's user avatar
  • 2,983
1 vote

NO display with raspberry Pi.High voltage at 3.3V output.(Is it dead?)

Power Problems A blinking red light indicates power problems. A blinking red power LED indicates problems with the power supply. On model A and B, it is hard-wired to the 3.3V power supply rail. ...
Hydraxan14's user avatar
  • 1,836
1 vote

Restore deleted files on Raspbian Jessie

DISMOUNT THAT CARD RIGHT NOW. It can be done, but let this be a lesson that there is no substitute for good backups. With the Rpi you are fortunate that you can use W32DiskImager periodically. If ...
SDsolar's user avatar
  • 2,348
1 vote

Can't access SD card contents (Ubuntu) after inserting SD into Android phone

What you see is just the Boot-Partition of your Pi. It is FAT32 and therefore can be read by your phone. The Root-Partition (with all your data) is of type Ext4. You don't seem to have mounted it or ...
kwasmich's user avatar
  • 2,702

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