[Courses] [FS] Lesson 5

[Christine Bussman]

Looking at my own fstab, I have a few questions.
(my fstab is located at the end of this email for reference)

1.  What does the 'notail' option do?  (I have that set on
several Reiserfs partitions)

2.  Why does my swap entry have 'none' in the second
column?  (and for that matter 'sw' in the fourth)

3.  What is the shm entry for?  The explanation in the file
is gibberish to me.

4.  Why the difference in the first column of proc?

I know some of this may be a distro specific issue, I
should probably note that I'm using gentoo linux.  This
means I had to fill in the details in a skeleton fstab while
installing, so some of these options might not be very
good, though they do all work.

This particular lesson was especially interesting for me,
because it makes all the 'magic' things I typed in while
installing make more sense.  It will also allow me to fix
some non-optimal options and to better be able to install
later (no trial-and-error).

Christine

my /etc/fstab (with comments left in for clarity)
(sorru for the formatting, it's due to the narrowness of
email compared to my file)

# NOTE: If your BOOT partition is ReiserFS, add the
notail option to opts.
/dev/hda1               /boot           ext2
noauto,noatime         1 1
/dev/hda3               /               reiserfs
noatime,notail         0 0
/dev/hda4               /home           reiserfs
noatime,notail         0 0
/dev/hda2               none            swap            sw
0 0
/dev/cdroms/cdrom0      /mnt/cdrom      iso9660
noauto,ro,user         0 0

# NOTE: The next line is critical for boot!
none                    /proc           proc           
defaults
0 0

# glibc 2.2 and above expects tmpfs to be mounted at
/dev/shm for
# POSIX shared memory (shm_open, shm_unlink).
# (tmpfs is a dynamically expandable/shrinkable ramdisk,
and will
#  use almost no memory if not populated with files)
# Adding the following line to /etc/fstab should take care
of this:

none                    /dev/shm        tmpfs          
defaults
0 0