What is your /etc/mtab?
Submitted by mcortese on Wed 23 Dec 2009
| a regular file |
   58% | 1096 votes |
| a link to /proc/mounts |
29% | 543 votes |
| something else... |
9% | 181 votes |
| Total 1864 votes |
[ Parent ]
What actually is the "something else"?
[ Parent ]
and which is more advantageous. Thanks in advance :D.
[ Parent ]
Is BSD mtab different than Debian Linux mtab?
How many ways has mtab been done?
[ Parent ]
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=494001
http://lkml.indiana.edu/hypermail/linux/kernel/0303.0/0415.html
Some discussions about mtab.
Still not really showing any other kind of mtab: file or link.
Is there anything else out there?
[ Parent ]
What are those something elses?
[ Parent ]
No! I think it was sarcastic. :)
[ Parent ]
[ Parent ]
Yes I know that from the manpages.
But I consider this poll's three choices to be totally different ways of implementing /etc/mtab.
I have used Slackware,RedHat,SUSE,Turbo,etc. as far back as about 1993.
Also the three BSD's, Net, Free and Open.
Currently I have only been using Debian stable since Potato.
I do not recall any of those distros using anything that fits the something else category.
The question is: What is something else?
[ Parent ]
But I'm still waiting to find out what those "something else" is/are.
Anybody care to describe a something else /etc/mtab?
[ Parent ]
[ Parent ]
Making it a symlink to a different dir allows /etc to be read only when not in the process of reconfiguring the system.
Making it point to a regular file rather than /proc/mounts enables mount features that store information in /etc/mtab not known to the kernel, such as which user mounted a cdrom, the loop mount logic and bind mounts.
Placing the regular file on tmpfs prevents old data from surviving a reboot and allows mtab to work before / or any other persistent file system has been mounted read only later in the boot process.
[ Parent ]
Making it point to a regular file rather than /proc/mounts enables mount features that store information in /etc/mtab not known to the kernel, such as which user mounted a cdrom, the loop mount logic and bind mounts.I think what you're saying was true in the past. There's no additional info in /etc/mtab than in /proc/mounts today. See Debian Bug #494001
[ Parent ]
[ Parent ]
Which *nix distributions actually use the something else option?
Does anyone know of an online published comparison of implemented methods?
This is an interesting poll; if only it had more feedback.
Thanks Steve, very usefull site.
[ Parent ]
I think that writing "stateful" data to a file in /etc is really ugly, and only understandable as a heritage of the old UNIX days. Just look at all the -n flags added to mount commands in various init scripts! This extra complexity wouldn't be needed, had /proc/mount worked correctly since the beginning.
[ Parent ]
Ah yes, it's a file that lists the currently mounted media...
[ Parent ]