sudo.8 mkfs(8) -t ext4 /dev/vdb1
execute a command as another user
build a Linux filesystem
-t, --type type
       Specify  the  type  of  filesystem  to  be  built.   If not specified, the default filesystem type
       (currently ext2) is used.

       Filesystem-specific options to be passed to the real filesystem builder.  Although not guaranteed,
       the following options are supported by most filesystem builders.
source manpages: sudomkfs