List block devices

Tree of disks, partitions, loop devices with filesystem info

lsblk -o NAME,SIZE,TYPE,FSTYPE,MOUNTPOINT,UUID

More linux commands

Show block device UUIDs

blkid

Print UUID, LABEL, and FSTYPE for all block devices
Mount a partition

mount -t ext4 /dev/sdb1 /mnt/data

Mount ext4 partition to /mnt/data
Show all mounts

findmnt --real

List all real (non-virtual) mounted filesystems in a tree
Remount filesystem read-write

mount -o remount,rw /

Remount the root filesystem as read-write (e.g. after rescue boot)
Check filesystem integrity

fsck -n /dev/sdb1

Dry-run fsck check (no changes); unmount first for a live fix