Understand parameters in /etc/fstab


Exemplar for fixed media file system

Read an interesting article from Dr. Brown’s Administration (January 2012 Edition). I have used the material inside to

If you look at your /etc/fstab file,  you may be wondering what are those parameter settings in the

LABEL=/home             /data                   ext3    defaults        1 2

Column 1 (“LABEL=/home“) – Label assigned to the filesystem when it was created

Column 2 (“/data“) – Mount point within the directory

Column 3 (“ext3“) – Type of filesystem. Supported types includes ext2, ext3, ext4, reiserfs, isi9660,nfs etc

Column 4 (“defaults”) – Mount Options. Valid options depend on the filesystem type

Column 5 (“1”) – Interpreted by the dump command if you use it to make backup (1 = Make backups, 0 = Do not)

Column 6 (“2”) –  The order in which fsck will check the filesystem at boot time. ( 1 = the root partition, >1 = non-root partition), 0 = no check which is appliable for removable media or NFS)

 

Exemplar for movable media

/dev/sdd    /media/dvdrom    auto   ro, noauto, user 0 0

Column 1 (“/dev/sdd”) – The name of the dvd-rom device

Column 2 (“/media/dvdrom”) – The mount point

Column 3 (“auto”) – Tell the kernel to determine the filesystem type automatically

Column 4 (“ro, auto, user”) –

  • ro -> read only
  • noauto -> don’t mount boot time
  • user non-root users can mount it (for security, the following option are implied
    • nosuid (do not honour the set-user-id bit on files)
    • nodev  (do not honour device file entries)
    • noexec (do not treat files as executable)

Column 5 and Column 6 as above.

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