A filesystem is a way to organize and store computer files with their data.

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EXT3 file system pre digest material

I am looking for understanding EXT3 filesystem source code. I think I need a little pre-digestion to fully understand the code. Can anyone please suggest some material(blog etc.) where I can get some ...
161
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4answers
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/usr/bin vs /usr/local/bin on Linux

Why are there so many places to put a binary in Linux? There are atleast these five: /bin/ /sbin/ /usr/bin/ /usr/local/bin/ /usr/local/sbin/ And on my office box, I do not have write permissions ...
3
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2answers
630 views

How to test file system correction done by fsck

How to make sure that fsck is correcting corruptions while keeping the integrity of file system? Suppose clients are writing lots of files through NFS to server, and there happens something that ...
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5answers
7k views

How to cache or otherwise speed up `du` summaries?

We have a large file system on which a full du (disk usage) summary takes over two minutes. I'd like to find a way to speed up a disk usage summary for arbitrary directories on that file system. For ...
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4answers
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Is it possible in bash, to start reading a file from an arbitary byte count offset?

I want to locate a date which is somewhere in an 8 GB log (text). Can I somewhat bypass a full sequential read, and first do binary splits of the file (size), or somehow navigating the filesystem ...
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289 views

Allowing user to read only parts of NTFS filesystem

After installing ntfs-3g I have an option in nautilus to mount a Windows directory but I need to give root password. While I have no objection to giving root password I would prefer to be restricted ...
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Reserved space for root on a filesystem - why?

I understand that by default, newly created filesystems will be created with 5% of the space allocated for root. I also know you can change the defined space with: tune2fs -m 1 /dev/sdXY What I'm ...
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2answers
571 views

How many entries are created when you make a new directory in *nix?

As per the question, I am thinking mkdir ~/a is either two or three: 1 entry for the dir it sits in (~/a) 1 entry for itself (cd a && ls .) and/or 1 entry for itself again (cd a && ...
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2answers
330 views

Choosing the file system to use with LVM

Since I found out about LVM I have been giving more thought to the process for choosing the file system for my future installs. Usually I'd always choose whatever default option the distro would ...
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3answers
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What file systems on Linux store the creation time?

Are there any (good known, reliable) file systems on Linux that store the creation time of files and directories in the i-node table? If there are, is the "changed" time replaced by the creation ...
5
votes
3answers
130 views

Network Filesystem + Local Access

I need to set up a network fs, so that I can mount a directory from Box A on to Box B and Box C. However, I need those files to not be transferred from Box A upon every access request; basically, I ...
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2answers
432 views

Swap root at runtime

I am developing an embedded Linux system. The system is usually installed by creating a ISO file which is written to a USB stick the board can boot from. To make the installation possible to do ...
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1answer
1k views

How to copy files nested in directories that match a pattern?

I'm looking to copy files from subdirectories that match this pattern vendor/plugin/*/tasks/*.rake into a folder lib/tasks I think that this could be done several ways, but wanted to see if a ...
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1answer
6k views

Where are the mount points defined in CentOS?

There is a mount point at /mnt/mountname and it goes to a large SAN with lots of storage but it's mounted as a read-only filesystem. I want to add a mount point with a different name that's ...
4
votes
3answers
410 views

What would be a good choice for an elastic file system (for adding storage at a later date)?

I'm currently running a Debian 6.0 server with EXT3, but I'd like to move over to Arch. It's being used as a file server right now with a 1TB drive in it (of which 650GB in it is used). What I'd like ...
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2answers
897 views

How to run e2image to backup a remote CentOS server?

Our server is hosted out of the country, I just have SSH access. I want to take an image backup of my server. I found the e2image utility to take an online backup of that server, but when I run ...
5
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1answer
303 views

Why do I need ntfs-3g when I have already enabled NTFS support in the kernel?

When configuring the kernel I see an option to add read-write support for NTFS. Then when mounting my NTFS partition I still have to install ntfs-3g and pass ntfs-3g as the type. I thought if I add ...
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2answers
341 views

How are directories managed in the filesystem?

On behalf of this particular question I would like to know how directories are managed in the file system. What does the author of the above question mean by telling each directory has n+2 ...
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3answers
2k views

Why does '/' have an '..' entry?

This just baffles me. Why does the root directory contain a reference to a parent directory? bob@bob:/$ ls -a . build home lib32 mnt .rpmdb sys vmlinuz .. cdrom ...
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3answers
2k views

Is there a limit of hardlinks for one file?

Is there a limit of number of hardlinks for one file? Is it specified anywhere? What are safe limits for Linux? And what for other POSIX systems?
2
votes
2answers
6k views

Formatting external drive in CentOS previously used on OS X

I have a USB key they I want to use on a CentOS box. The USB key was previously used on OS X so I want to erase it to make it writable by CentOS. Can someone help me with the commands I need to run? ...
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vote
1answer
2k views

Compared to other filesystems why is ZFS so slow, with incoming data?

Ok. I get about 1/3 of the speed on the same drives when using ZFS. Now, I understand that ZFS is self-healing and that everything is also stored with its hashes. This makes it safer to use. I ...
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4answers
2k views

How to setup a “data” partition shared by multiple Linux OS'es?

Currently I have a NTFS partition that contains shared data. My rationale is, NTFS doesn't have any idea about file permissions, so I won't have any trouble using them in a multi-boot system ...
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2answers
1k views

How to repair an ext3 partition after broken resize operation?

I was using gparted to resize a near-terabyte ext3 partition, adding about 40 GB to the left. After nearly 12 hours of moving data (and with 23 more hours estimated to remain) the system hung. Now ...
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2answers
14k views

How do you make samba follow symlink outside the shared path

This is Ubuntu server 10.04 64 and samba 3.4.7. I have a shared directory /home/mit/share and another one /home/temp that I link into the shared one: ln -s /home/temp /home/mit/share/temp But on ...
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1answer
7k views

Mount samba filesystem into RHEL 5.5

I have a trial RHEL version for a proof of concept where I was asked to mount a windows filesystem into linux. I tried mount -t smbfs -o username=samba,password=samba //Desktop/Public /mnt/public ...
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1answer
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What is an inode? [duplicate]

Possible Duplicate: What is a Superblock, Inode, Dentry and a File? Documentation of Unix-file-systems contains often the term 'inode'. What is that and what does that? Why have ...
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3answers
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What is the difference between procfs and sysfs?

What is the difference between procfs and sysfs? Why are they made as file systems? As I understand it, proc is just something to store the immediate info regarding the processes running in the ...
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1answer
1k views

What is the significance of Linux's Disk caching Mechanisms?

I would like to know the exact meaning and significance of Linux's Disk caching Mechanisms. In one of the articles I have read, page cache and dentry cache are two forms of them. Could somebody ...
4
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1answer
7k views

e2fsck: unable to set superblock flags on LogicalVolume

When I boot my machine either in normal mode or runlevel 1 it throws following error and I'm unable to boot the machine: checking filesystems /dev/MyGroup/LogVol00: UNEXPECTED INCONSISTENCY; RUN ...
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5answers
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What is a Superblock, Inode, Dentry and a File?

From the article Anatomy of Linux File Systems by Tim Jones, I read that Linux views all the file systems from the perspective of a common set of objects and these objects are superblock, inode, ...
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1answer
370 views

What is the typical file limit of a folder on *nix file systems?

Obviously, if you stick a lot of files in one folder, the efficiency of various file operations is going to go down (e.g. ls takes a lot longer). However, what's the limit for how many files you can ...
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What are the benefits and downsides to use FuseFS filesystems?

I know some filesystems present themselves through Fuse and I was wondering about the pros and cons to this approach.
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2answers
359 views

How is file ownership affected across different systems?

As I understand Unix file systems, any file on a unix system must belong to a group and a user of the said system. A file cannot belong to a group or user that does not exist on the system. From that ...
3
votes
1answer
411 views

Are there any differences between mounting a /proc filesystem inside a chroot compared to mounting it from the outside?

Compare the following: mount -t proc none ./my_chroot/proc and: chroot ./mychroot mount -t proc none /proc
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2answers
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Why does truncate fail for sizes above 2043G in ext3?

Why does this work: truncate -s 2043G foo ...while this fails: truncate -s 2044G foo Why 2043 gigabytes, of all values?
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1answer
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Number of files per directory

I have a directory with about 100000 small files (each file is from 1-3 lines, each file is a text file). In size the directory isn't very big (< 2GB). This data lives in a professionally ...
2
votes
1answer
691 views

immutable-like flag for perms

Is there any chattr flag that would allow me to lock a file's unix permissons, and not change them without resetting the flag? The file itself should still be modifiable, I just want to prevent ... ...
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4answers
143 views

Linux compability file system

I need to develop a file system for Linux for my diploma work. Where can I find infomation about this theme? How can I test it and other?
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1answer
3k views

what does the “a” in chattr +ia do?

what does the a in chattr +ia <filename> do? and why would you add the a in combination with the i? note: I know the i is for immutable
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2answers
840 views

Mount windows Users directory as /home in linux virtual machine

I'm setting up a laptop for a friend and I'm going to put linux on it in a virtual machine and I want to make it as seamless as possible. I've mounted the \Users\Username directory in a VM before and ...
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2answers
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root user denied access to .gvfs in rsnapshot?

I was running rsnapshot as root and I got the following error. Why would this happen? what is .gvfs? rsnapshot weekly slave-iv ...
6
votes
2answers
927 views

I/O-overhead of dm-encrypted device?

What would be the Read-/Write-overhead when using dm-crypt (LUKS) as full disk-encryption (including root partition) on a Linux-Desktop (Ubuntu)? I plan to stack it like so: LUKS > LVM > ext4 The CPU ...
14
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1answer
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How do you use badblocks?

I need to do a destructive (rw) test on a new drive, and a read-only on a drive that fell out of my RAID array. I want to see if it finds problems and how far along it is.
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votes
2answers
887 views

NTFS Junctions and Unix Hard Links

I'm building an IO abstraction library for CIL code, and I have a very hard time understanding the differences between a junction between two folders in NTFS and hard links. Are they equivalent? Are ...
5
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6answers
261 views

What's the best tool chain or single tool to transform a NTFS to ext[n] filesystem?

I've decided to go Linux only, finally! This also means that I have a bunch of disks still under NTFS. I don't have spare space anywhere to transfer the files to and then just re-format the drive so ...
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2answers
4k views

understanding “mount” as a concept in the OS

I want to understand what mounting is. It is used in different contexts and situations and I can't find resources which: Describe the mount concept Explain the actions taken by the ...
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6answers
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What is the use/meaning of 'swap area' while linux installation?

When i installed ubuntu in my x86 machine, I had to configure some memory as 'swap area'. What is the use of this memory and what is the importance of this memory in linux file systems? How can I ...
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1answer
372 views

error using “du” command

I am on the university machine trying to estimate the disk usage I have on my space I do du -csh ./ from the begining of my account, but an error is given that ./Yesterday/Yesterday is not a ...
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1answer
146 views

Strategies for maintaining a reference to a file after it was moved or renamed?

I've had a mac at work lately, and was amazed to see that Xcode would still find my latest project after I renamed its folder and moved it someplace else. Now I understand that this is the result of ...