Welcome to the most active Linux Forum on the web.
Go Back > Forums > Linux Forums > Linux - Newbie
User Name
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!


  Search this Thread
Old 01-09-2009, 03:20 PM   #1
LQ Newbie
Registered: Jan 2007
Distribution: Multiple
Posts: 7

Rep: Reputation: 0
Question about definition of 'filesystem'

Not-quite-a-newbie, here; I actually manage a number of Linux Boxes and I've been tasked with setting up a new server with an eye towards future expansion -- so my question is about filesystem limits. I ask here in this forum because it's one of those 'basic' questions that I never asked.


What is meant by 'filesystem', when we are informed that the maximum filesystem size under ext3 is 32TB, what is meant by 'filesystem'?

Does it mean:

Everything under / including mounted remote volumes?

Anything on one block device, no matter how it is partitioned?

Any named volume group?

Or does it mean something else?

The budget proposal for the archives' hardware depends on the answers!



Edited for Clarity:

Thanks for the replies, but I think I need to offer some clarification:

Of course wikipedia has a definition of 'filesystem' -- but it's too general. manpages sometimes refer to volumes as filesystems, sometimes to everything under root (/) -- it's not consistent, and therein lies my problem.

I think what I'm asking about is related to address-space.

Some references call anything mounted under / the 'filesystem'. Other references call anything mounted under / (such as /etc or /home or /tmp) different 'filesystems', and this is especially true when each one (/etc /home /tmp) is mounted on a different volume.

So, is it the individual volumes (/etc /home, /tmp ) that are limited to 32TB (The stated Maximum for an ext3 filesystem is 32TB), or is it the total aggregate size under / that is limited to 32TB?

What is the definition of filesystem -- I need the definition, not connotations or common assumptions about it.


Last edited by Fionnbharr; 01-10-2009 at 11:24 AM. Reason: Clarification of Question
Old 01-09-2009, 03:37 PM   #2
LQ Veteran
Registered: Nov 2005
Location: Annapolis, MD
Distribution: Arch/XFCE
Posts: 17,802

Rep: Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738
I am sure that wikipedia has a definition of "filesystem".

To me a filesystem is a set of bookeeping stuctures that are written to a disk partition which then allow you to read and write files with relatively user-friendly commands. The interface (driver) for these structures has to be in the operating system. It is analogous to telling a printer to print something---intermediate code (driver, firmware, etc.) gets you to the pulses that are sent to the ink jets.)
Old 01-09-2009, 09:24 PM   #3
Registered: Jan 2005
Location: Midwest USA, Central Illinois
Distribution: SlackwareŽ
Posts: 12,898
Blog Entries: 27

Rep: Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185Reputation: 2185

A good definition;

excerpt from file system;

(1) The method for storing and retrieving files on a disk. 
It is system software that takes commands from the operating
system to read and write the disk clusters (groups of sectors).
The file system manages a folder/directory structure, which
provides an index to the files, and it defines the syntax used
to access  them (how the "path" to the file is coded). File
systems dictate how files are named as well as the maximum size
of a file or volume.

There are numerous file systems in use; for example,
FAT32 and NTFS are Windows file systems, and HFS is used on
Macs. Linux uses ext2, ext3 and FAT32. Unix systems use UFS,
ext2, ext3 and ZFS. See cluster, path, FAT32, NTFS, HFS, NFS,
UFS, ext, ZFS and hierarchical file system.

(2) A data processing application that manages individual files.
It opens, closes, reads and writes the file as a single entity.
In a file system, files are related to each other by customized
programming (customers to orders, vendors to purchases, etc.).
Contrast with a "relational database," which has built-in
constructs that can more easily form these relationships. For
example, they can be used to join files together and split them
apart, all without tedious programming. See relational database
and DBMS.
To the OP, Google can get you a lot!
Old 01-09-2009, 09:33 PM   #4
LQ Veteran
Registered: Aug 2003
Location: Australia
Distribution: Lots ...
Posts: 15,988

Rep: Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217Reputation: 2217
KISS - that what is the output of "mkfs" (or format in some other place). Allows the OP to answer all the original questions.
Old 01-09-2009, 10:05 PM   #5
Registered: Jul 2007
Location: Scunthorpe, UK
Distribution: Ubuntu 8.10; Gentoo; Debian Lenny
Posts: 961

Rep: Reputation: 69
Ext3 has a max size between 2 and 16tb, depends on other factors- mainly block size.

The limit is volume size, due to the size set aside for addressing etc., so you could have 100 1tb drives mounted on a system thats on a 1gb hard drive and use it like that, There'd be no problem at all- each 1tb drive would not affect the 1gb drive in such a system.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Postfix definition question. swamprat Linux - Software 2 05-11-2008 12:49 AM
Red Hat 9 h.c.l. modem definition question. Hal Linux - Hardware 2 01-16-2004 05:07 PM
Filesystem question log Linux - General 5 06-13-2003 03:13 AM
Two C question: definition of veriable and powerplane Programming 4 05-01-2003 11:59 PM
Alias definition question Dark_Helmet Linux - General 5 02-04-2003 03:48 PM > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 11:51 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration