fstab

Updated: September 28, 2024

File systems table is used for configuring mounts within a Debian system.

Table of Contents

Terminology

Term Meaning
defaults rw, suid, dev, exec, auto, nouser, and async
async I/O to fs done outside of main program flow
atime turns off noatime
noatime do not update inode access times
auto can be mounted with -a
noauto can only be mounted expicitly ( -a will not cuase the fs to be mounted)
dev interpret character or block special devices on fs
nodev do not interpret character or block special devices on fs
diratime update directory inode access times (default)
dirsync All dir updates done sync. Affects system calls: create, link, unlink, symlink, mkdir, rmdir, mknod and rename.
exec permit execution of binaries
noexec bianaries not allowed to execute
group Allow non-root users to mount fs if user is apart of group of device
encryption Used with loop option: specify an algorithm
keybits specify keysize to use with encrytion algorithm
iversion everytime the inode is modified, i_version will be incremented
noiversion do not increment i_version
mand allow mandatory locks on fs
nomand do not allow mandatory locks on fs
_netdev fs resides on a device that requires network access
nofail do not report errors for the device if it does not exist
relatime update inode access times relative to mtime or ctime
suid allow set-user-identifier or set-group-identifier bits to take effect (rather unsafe)
nosuid do not allow suid
silent turn on silent flag
loud turn off silent flag
owner allow non-root user to mount fs if the own the device
remount attempt to mount an already mounted fs ( usually used to make a readonly fs writable
ro read only
rw read write
sync can cause life cycle shortening eg flash drives
user allow ordinary user to mount fs
nouser forbid non-root users to mount or unmount fs
users Allow every user to mount and unmount the filesystem implies: noexec, nosuid nodev

ARGUMENTS

mount
  -V, --version
  -h, --help
  -v, --verbose
  -a, --all             # mount all fs in fstab
  -F, --fork
  -f, --fake            # dry run
  -i, --internal-only   # do not use /sbin/mount.filesystem helper
  -I                    # add labels to mount output
  -n, --no-mtab         # mount w/o writing to /etc/mtab  (needed if /etc is on ro fs)
  -p, --pass-fd         # in case of loop mount  with encryption, rad the pw from file desciptor num                         in stead of from the terminal.
  -s                    # sloppy mount, tolerate failed options
  -r, --read-only       
  -w, --rw
  -L _label_            # mount parition with specified label
  -U _uuid_             # mount parition that has a specified uuid (require /proc/partitions)
  -t, --types
  -O, --test-opts
  -o, --options
  -B, --bind            # remount a subtree somewhere else so that its contents are available in                            both places
  -R, --rbind           # remount a subtree and all possible submounts somewhere else so that all                           its contents are available in both places
  -M, --move            # move a subree to some other place

/etc/fstab

<device name> <mount point> <fs type> <mount options> <dump> <fsck>

fs type: has option for auto to detect file system type
mount options: see term below: mainly auto/noauto exec/noexec user/nouser etc
dump: 0 = excluded from taking backup <0 = device will be backed up
fsck: 0 = excluded from fsck <1 = device will be fsck after root (1) 

/dev/sdb1 /storage/disk2p1 ext4 defaults 0 0

or for uuid

UUID=7df7df7-dfdf7d-dfdfdfy-7686 /var/www ext4 defaults 0 0