Formatting

BE CAREFUL: FORMATTING WILL ERASE ALL EXISTING DATA!

formatting means create a FS.

mkfs.ext4 /dev/sdb1
mkfs -t ext4 /dev/sdb1

check a disk with mkfs, looks for bad element meaning the diskend of life:

mkfs -t ext4 -c /dev/sdb1

-m: % reserved space to prevent user to fullfill disk.

SWAP formatting

mkswap /dev/sdbX #format
swapon /dev/sdbX #tell system to use it as swap