4d1l
Posts: 5
Joined: Sat Apr 21, 2012 10:27 am

Kernel Panic : VFS :Unable to mount root fs on unknown-block

Mon Jul 23, 2012 2:10 pm

Hi,

When I boot up the Pi I always get Kernel Panic: VFS : Unable to mount root fs on unknown-block (179,2). This has happened to every operating system except Raspbmc. Its been like this since first boot. I am using 32gb Memory Card. Can someone please help. :?

tlimited
Posts: 1
Joined: Sun Jul 29, 2012 9:01 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Sun Jul 29, 2012 9:18 pm

I have the exact same problem on boot!

Pi worked perfectly on both wheezy and now raspbmc on a Scandisk SD 8gb class 10, and apple iphone charger. But suddenly, maybe caused by using Constellation as a remote for turning on/off Pi, the Pi don't boot just as 4d1l describes.

If any one has a solution or an idea, please help! Don't want to lose all my configurations.

miicchhii
Posts: 3
Joined: Fri Aug 03, 2012 11:57 am
Contact: Website

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Fri Aug 03, 2012 11:59 am

I have the same problems on raspbian wheezy, since i used the GPIO's over php and shellscript.

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tony1tf
Posts: 49
Joined: Tue Jul 03, 2012 12:33 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Fri Aug 03, 2012 6:22 pm

I was posting my problem under Raspbian Wheezy, but just discovered this thread.
I had a USB hub problem losing keyboard and mouse after a while, but after much experimentation, powering on and off, using a different mouse, with and without the hub etc, I now have an unbootable RPi even with no hub, k/b or mouse - error is:
PANIC: VFS Unable to mount root fs on unknown-block (179,2)
Entering kdb (current=0xcb846c80, pid 1) due to Keyboard Entry

I tried changing to the original distribution on a 2GB SD card in case I had scrambled Wheezy, but get a similar error:

No filesystem could mount root, tried: ext4
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block (179,2)

I have used several power configurations, with i/p volts between 4.93 and 4.97V, so I dont believe I have a problem there, and in any case it was working before.
So it looks like the RPi is bricked.
Any help welcomed.
Tony

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tony1tf
Posts: 49
Joined: Tue Jul 03, 2012 12:33 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Fri Aug 03, 2012 7:22 pm

Reference my previous post, I was reading R-Pi trouble shooting on the elinux.org website. This mentions the Kernel Panic problem and suggests removing any USB devices. I have booted my device with and without USB and it makes no difference. I also just tried a bigger power supply (5V 2A Samsung) which gives 5.19V on the i/p to the polyfuse and 5.09 on the regulator side. Still get same error. So is there anyone from the R-Pi org or Element14 looking at this thread and able to respond.

Tony

User avatar
tony1tf
Posts: 49
Joined: Tue Jul 03, 2012 12:33 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Fri Aug 03, 2012 8:22 pm

OK folks. Sorry to answer my own post again, but some of you out there may still be in the same state as I was. Reading the elinux.org website again, I found a reference that low voltage on the supply or feeds from the USB ports can cause unexpected writes to the SD card (I cant currently find the reference). I was wondering if both my SD cards has experienced such a write glitch. So I rewrote the Wheezy image to my 16GB Transcend class 10 card from my Macbook and Pound shop card reader. My setup also seems to need the init file editing to force the HDMI TV o/p.
Hey presto - working Pi again.
So now I have to reload the work I was doing, since any previous code seems to be lost.
So the answer to this topic - at least for me - is to rewrite the SD card image

good luck out there
Tony

4d1l
Posts: 5
Joined: Sat Apr 21, 2012 10:27 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Sat Aug 04, 2012 5:14 pm

miicchhii wrote:I have the same problems on raspbian wheezy, since i used the GPIO's over php and shellscript.
To fix this problem get a new SD card or did what "tony1tf" did.
OK folks. Sorry to answer my own post again, but some of you out there may still be in the same state as I was. Reading the elinux.org website again, I found a reference that low voltage on the supply or feeds from the USB ports can cause unexpected writes to the SD card (I cant currently find the reference). I was wondering if both my SD cards has experienced such a write glitch. So I rewrote the Wheezy image to my 16GB Transcend class 10 card from my Macbook and Pound shop card reader. My setup also seems to need the init file editing to force the HDMI TV o/p.
Hey presto - working Pi again.
So now I have to reload the work I was doing, since any previous code seems to be lost.
So the answer to this topic - at least for me - is to rewrite the SD card image

good luck out there
Tony
It seems my SD cars was not supported. Bought a new SD card and works like a charm.

MothBox
Posts: 19
Joined: Mon May 28, 2012 7:11 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Tue Aug 07, 2012 1:33 pm

I have the same problem when booting Xbian for the 2nd time.

My SD card is on the approved list though: 8GB SDHC Class 10 (SD10V/8GB).

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RaTTuS
Posts: 10103
Joined: Tue Nov 29, 2011 11:12 am
Location: North West UK

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Tue Aug 07, 2012 1:36 pm

you may be able to recover just by replacing the DOS partition -
the kernel , or start.elf may have got currupt somehow
How To ask Questions :- http://www.catb.org/esr/faqs/smart-questions.html
WARNING - some parts of this post may be erroneous YMMV

1QC43qbL5FySu2Pi51vGqKqxy3UiJgukSX
Covfefe

alanben75
Posts: 1
Joined: Wed Oct 03, 2012 2:11 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Thu Oct 04, 2012 5:28 pm

I was getting the same problem. I ended up doing a few things, so I'll list them. Hope this helps.

I kicked off with SD formatter. Re formatted the SD disk. In option I selected 'adjustment' on.

I then reinstalled (in windows 7) raspbmc.
I did the same for Debian on a different SD card (this one was an old one that is only a class 4).

I did the next step for both SD cards.

I opened (in windows) the SD cards and edited the config.txt file. I added the following line

avoid_safe_mode=1

Then saved the file.

I then unmounted the SD card(s) from windows, and put it in the raspberry pi.

Plugged in the power, and they restarted, and raspbmc re installed.

Hope this helps,

Alan

chewie
Posts: 1
Joined: Thu Nov 01, 2012 10:44 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Thu Nov 01, 2012 10:58 am

Hi i got the same / similar problem using some builds of XBMC on my pi.

I ended up in reformating everything as soon as I run into this problem.
Until recently ..
As i tried to image my xbmc XD card (8GB) using dd (e.g. dd if=/dev/sdd of=image.dd) i run into the same effect after restoring from a Delking 8 GB SD (which i took out of my Canon EOS) to a more "stable" Samsung 8GB SD (mb-ss8a).

I got this unable to mount unknown-block(179,3) error ...

So by using two different SD cards one easily can see that 8GB are not always 8 GB -- there are some block more on the Delking than on the Samsung -> resulting in this error.

I took the defective Samsung card to my notebook mounting it resulting in some error massages in dmesg ..

to fix this problem I checked the filesystem
fsck.ext4 /dev/mmcblk0p3
answering yes to start a fix on a not fitting file system
resize2fs /dev/mmcblk0p7 7300M
Guessing the FS to 7.3GB

Insert the SD into you Pi and try :)

It worked for me on some cards -> maybe the error is the same on single cards and different cards as the systems is "loosing" blocks in SD .. leading to "corruption"..

good luck
chewie

haikin
Posts: 1
Joined: Thu Dec 13, 2012 11:19 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Thu Dec 13, 2012 11:33 am

My Pi encounter this problem twice..it runs normally for sereval days.
but, when i reboot, it crashed..
i have changed a sd card, but this problem appears again~
This is too bad..

kielstr
Posts: 1
Joined: Thu Dec 20, 2012 7:05 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Thu Dec 20, 2012 7:11 am

Hi,

Had the same problem. Put the SD card into my Ubuntu laptop and executed a fsck

e2fsck -f -v /dev/mmcblk0p2

Answered yes to all reported problems and my PI booted up OK.

-Kiel

mrbgturner1
Posts: 1
Joined: Thu Dec 20, 2012 12:15 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Thu Dec 20, 2012 12:32 pm

Hi

I am getting the same error. Get the Raspberry logo followed by error on first boot up.

Using a 4GB card Sandisk card pre- formatted at FAT32. Now instead of FAT 32 the card is saying its FAT16 and 17 mBytes are used out of 58Mbytes?

1) I have downloaded 2012- wheezy..... .img and unzipped
2) Ran DD instructions on website using a MACbookpro
3) Now have a FAT16 formatting SD card with the following files
2 x bin files
1 x cmdline
1 x config
1 x issuetext
3 x kernel file
2 x start file

Not a great start :)

Any clues please :) ?
Thanks
mrbgturner

sansjunk
Posts: 7
Joined: Fri Dec 28, 2012 12:27 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Fri Dec 28, 2012 7:17 pm

Just got my Pi after waiting a month. Ran into the same error even after writing the image multiple times. Turns out the SD card I was using was too slow (Class 2 SanDisk). I then tried with SanDisk class 6 (Extreme III) and it booted fine.

spitecho
Posts: 24
Joined: Tue Jul 10, 2012 12:03 am
Location: internet

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Fri Jan 04, 2013 11:11 am

I had this happen after an rpi-update. When I plugged it into another Linux box, it gave me an error on /dev/sdc2, so I ran:

Code: Select all

sudo fsck.ext4 -fy /dev/sdc2
Fixed it right up without formatting.

billotronic
Posts: 1
Joined: Sat Jan 05, 2013 2:47 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Sat Jan 05, 2013 2:56 pm

Fixing ext4 is all fine and dandy, but what is the source of the corruption? Really undermines the utility of the pi.

therealcharbs
Posts: 1
Joined: Mon Jan 07, 2013 12:14 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Mon Jan 07, 2013 12:16 pm

Hi all,

I was having this same problem and I thought I'd just mention that removing my USB devices (in my case a 3rd party IR dongle and a Logitech bluetooth dongle) fixed the issue for me.

jquan
Posts: 7
Joined: Sun Jan 13, 2013 6:40 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Sun Jan 13, 2013 6:47 pm

I fixed this error in 5 min, by reloading the image on the sd card.

rmomota
Posts: 2
Joined: Sat May 04, 2013 9:00 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Sat May 04, 2013 9:14 am

This keeps happening to me and the only (really the only) solution is format and re-install SD card.
I've a new Class 10 8GB SD card, it's already the 2nd SD card and still behaves the same way.
It happens occasionally after a XBMC automatic update on boot.
I think that this equipment is not prepared for massive read/write operations and this is where this system update fails.
Since the update is a critical operation it should in my opinion check the filesystem consistency after doing it and repeat it in case there are errors.
It happened once during boot, it shows a message saying that the partition is ReadOnly and loops until I turn it off.
I always use the reboot option from RaspBMC menu and it happend yesterday again.
I also tried to fix the partition with fsck, it really found lot errors and after fixing the kernel panic message was resolved but the system does nothing but displaying a berry in the screen.

crozone
Posts: 12
Joined: Mon Jul 30, 2012 11:27 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Tue May 14, 2013 12:14 pm

Okay, so I've been having this problem too. At first I thought it was just a warn out SD card, and that the same blocks were corrupting on write (my pi wouldn't even reboot after a fresh install and an apt-get dist-upgrade).

I took the measure of moving my entire ext4 system partition onto an external HDD and reconfiguring cmdline.txt to boot off it, only using the SD card for the fat32 firmware partition. All was going well, and the Pi was running much faster off the hdd than the SD card. Just when I thought I had it licked, I got the same Kernel Panic on blocks 8, 2. Couldn't mount /dev/sda2.

I have some weird feeling that this is a deeper bug than simply SD cards wearing out or low voltage over the USB ports. My voltage is a solid 4.9V and the external HDD has its own power supply (It's a standard laptop HDD over a USB->ATA bridge). It happens very quickly (after only a few reboots) and is incredibly frustrating. Also, I did extensive testing on the original problem SD card from my PC, and could turn up no read/write or filesystem errors (after something like 50 full read/writes), which supports this idea.

I'm running the latest standard Debian (2013-02-09-wheezy-raspbian.img) image with the latest firmware (as of this post)

EDIT: Nevermind, turns out my USB printer was causing the USB HDD to disappear completely from /dev/. The rest still stands though.

DavidWG
Posts: 1
Joined: Tue Jul 02, 2013 1:05 am

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Tue Jul 02, 2013 1:46 am

I just had the same problem running RaspBMC. My corruption was caused by the USB hot plug issue when I plugged in a Wireless dongle.

http://therandomlab.blogspot.com/2013/0 ... wn-on.html

I wasn't aware of that issue before that.

In any case "fsck" came to the rescue after I ran it on both the /boot and / partitions on the SD card. No more hot plugging for me!

tRoller
Posts: 3
Joined: Wed Jan 30, 2013 5:00 pm
Location: Slovenia

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Wed Jul 10, 2013 6:32 pm

Hi guys!

I have the same problem. I'm running XBMC on my RPi and when I plug it in, I only see the message:

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,2)

I see that some of you managed to resolve the issue with "fsck". Since I'm a real noob with Linux (apart from RPi, I only have this Win7 PC), I need your help. Is there a tool for Windows with which I might try fixing the problem?

Thanks for your help.

Best regards,
tRoller

WayneC
Posts: 3
Joined: Wed Jul 31, 2013 10:22 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Wed Jul 31, 2013 10:52 pm

Help... My RPi been running Raspbmc fine for weeks until this week's raspbmc july update.... now I'm getting the same error

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,2)

It's on a 8GB SD card with NOOB and it wouldn't go into recovery mode using Shift, so tried other 4GB SD card just running Raspbian and it all works fine and same on another 4GB card just running Raspbmc alone works fine even folllowing the update...

So using the tips on this thread I re-formatted the SD Card using the formatter and re-installed the latest NOOBS and re-selected Raspbmc... and exactly the same again. i've tried all the unplugging USB devices... but my power supply is usually ok...

What is the point of this... a complete evening wasted trying to fix something that was fine before the update?

and WHY does it need to update immediately when I download the latest software.?...

I assume my 8GB SD card is trashed somehow?

WayneC
Posts: 3
Joined: Wed Jul 31, 2013 10:22 pm

Re: Kernel Panic : VFS :Unable to mount root fs on unknown-b

Wed Jul 31, 2013 11:27 pm

Tried it again... it happened again.... so I re-copied the files on the pc to the SD card... whch forced a re-start of the NOOB choice and this time went with OpenELEC and it all works fine?

Think I just need to avoid Raspbmc on the NOOB card... Anyone know why?

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