Solving common disk errors

Any of these problems can be solved by following the given procedure

It is always good to copy db folder before doing any disk error fixing.
First boot using Clonezilla bootable usb drive and login to the command shell (Ctrl+Alt+F1).

1. Solving bad sector error

sudo -s
fsck.ext4 -y /dev/sda
or
fsck.ext4 -y /dev/mmcblk0

2. Fill disk with zeros to reset all data from disk

sudo -s
dd if=/dev/zero of=/dev/mmcblk0
or
dd if=/dev/zero of=/dev/sda

3. Fix corrupted superblock:

sudo -s
fsck.ext4 /dev/mmcblk0p1
or
fsck.ext4 /dev/sda

4. Fix mmc failure during booting. This has to be done from Saleculator command shell.

echo "options sdhci debug_quirks=0x40" >> /etc/modprobe.d/sdhci-pci.conf
reboot