Kernel panic - not syncing: VFS: Unable to mount root fs on


3 posts
by nealcg » Sun Jul 16, 2017 8:29 pm
]Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,7)

I have my new Pi 3 set up the way I like and decided to make a duplicate SD card as a backup.

I created a disk image using the Unix terminal dd command on my Mac and appear to have created a disk image . I then reformatted a second sd card and using the reverse operation in terminal appear to have copied this backup.img with two partitions onto the SD card. Everything appears to be right. The new sd card has two partitions "boot" and "RECOVERY" as expected - but!! when I put the duplicate card into my Raspberry Pi I get the Kernel panic error message shown above during the boot process.

I have tried running the disk repair utility on the duplicate card with no success.

The duplicate card has only 16 G while the original card has 32 G, but only a small fraction of the space is used and therefore should fit.

I would greatly appreciate some advice - thanks
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by rpdom » Mon Jul 17, 2017 8:07 am
nealcg wrote: The new sd card has two partitions "boot" and "RECOVERY" as expected

That doesn't sound right to me. The "RECOVERY" partition usually indicates a NOOBS installation where I would expect four or five partitions minimum. Also 179,7 refers to partition 7 on the SD card.

nealcg wrote:The duplicate card has only 16 G while the original card has 32 G, but only a small fraction of the space is used and therefore should fit.

Unless you have used something like gparted to resize the partitions to fit in under 16GB, you can't just copy part of the card and expect it to work on a smaller card.

Use the "piclone" SD card copier. It is smart and will resize eveything to fit on a smaller card (if it can).
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by billis2020 » Mon Jul 17, 2017 6:45 pm
You need to reflash the image of your current OS
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