Recovering MySQL InnoDB after power failure

Once, after the power was turned off, the UPS was discharged, then the generator automatic start did not work because it turned on and off several times, as a result, the server with MySQL was also started and disconnected from the power supply several times, later the tables of different databases were damaged , including the default database with mysql users, as a result, the MySQL daemon did not start.

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WS-SUP720-3BXL does not start Not Applicable Unknown

Once after a power outage, on Cisco Catalyst 6509-E, instead of the main module WS-SUP720-3BXL, only the backup module was launched.
As I found out later, the memory card stopped working and, accordingly, the module could not start the firmware. At this moment on the module all the indicators glowed red.

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Recovering file systems using fsck

Fsck (File System ChecK) – checks and restores file systems.

Before starting the scan, unmount the file system with the command:

umount /dev/sda1

An example of starting a scan (where /dev/sda1 is a device or partition to be checked):

fsck -V -C -f /dev/sda1

View brief documentation:

man fsck

I will describe some startup keys:
-C (display progress bar if possible)
-M (do not check mounted file systems)
-p (auto mode)
-y (agree to all questions)
-n (disagree on all questions)
-f (forced check)
-V (more detailed information)