# Pastebin YqYN7PGp
```root@rescue:~# mkfs.ext4 -L nixos /dev/sda1
mke2fs 1.42.12 (29-Aug-2014)
/dev/sda1 contains a linux_raid_member file system
Proceed anyway? (y,n) y
/dev/sda1 is apparently in use by the system; will not make a filesystem here!
root@rescue:~#```