A file system (or filesystem) is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device(s) which contain it.

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LVM dangers and caveats

I have recently started using LVM on some servers for hard drives larger than 1 TB. They're useful, expandable and quite easy to install. However, I could not find any data about the dangers and ...
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7answers
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du vs. df difference

I have a fileserver where df reports 94% of / full. But according to du, much less is used: # df -h / Filesystem Size Used Avail Use% Mounted on /dev/sda3 270G 240G 17G ...
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How to workaround the NTFS Move/Copy design flaw?

As anyone that has dealt with file server permissions is aware, NTFS has an interesting design feature/flaw known as the Move/Copy problem. As explained in this MS KB article, the permissions for a ...
29
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1answer
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Why are my XFS filesystems suddenly consuming more space and full of sparse files?

I've run XFS filesystems as data/growth partitions for nearly 10 years across various Linux servers. I've noticed a strange phenomenon with recent CentOS/RHEL servers running version 6.2+. Stable ...
36
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7answers
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What is the best Linux filesystem for MySQL (InnoDB)?

I tried to look for benchmark on the performances of various filesystems with MySQL InnoDB but couldn't find any. My database workload is the typical web-based OLTP, about 90% read, 10% write. Random ...
4
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1answer
4k views

How to format XFS parition if the stability is the most important thing

We want to use XFS to format some partitions in a server. High performance is of course our goal, but we prefer to stability firstly. For example, we want to recover the FS quickly if power failure ...
2
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2answers
6k views

How to recover XFS file system with “superblock read failed”

I have a disk from a Buffalo LinkStation that has an XFS partition on it that I cannot mount. Plugging the disk into an SATA->USB caddy on an Ubuntu box. I get the following: $ sudo fdisk -l ...
4
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1answer
2k views

NFS - Files on client are not appearing on server

Heres my set up: One NFS Server machine, two NFS client machines. The client machines write files to the NFS mount, but occasionally, the files don't appear on the NFS Server machine or other client ...
16
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8answers
1k views

Optimal UNIX File System Partition + Setup Strategy

When partitioning a new system disk(s) for UNIX, what is your prefered strategy for both desktop and/or servers? Please include disk partition layout, file system format(s) and options, mount points, ...
6
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4answers
2k views

Distributed, Parallel, Fault-tolerant File System

There are so many choices that it's hard to know where to start. My requirements are these: Runs on Linux Most of the files will be between 5-9 MB in size. There will also be a significant number of ...
13
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7answers
8k views

Copy permissions to identical tree on linux / unix

i have a tree of files with correct permission. then i have a (filewise) identical tree (with different file contents tough) with wrong permissions. how can i transfer the permissions layout from ...
20
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5answers
2k views

Turning off atime on a filesystem

I am setting up a mongoDB replica set and one of the first things I am suppose to do is turn off atime on the file system. After researching this a bit, I am not opposed to doing this, but I have to ...
20
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9answers
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Maximum number of files in one ext3 directory while still getting acceptable performance?

I have an application writing to an ext3 directory which over time has grown to roughly three million files. Needless to say, reading the file listing of this directory is unbearably slow. I don't ...
17
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9answers
18k views

Best way to compare (diff) a full directory structure?

What's the best way to compare directory structures? I have a backup utility which uses rsync. I want to tell the exact differences (in terms of file sizes and last-changed dates) between the source ...
13
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8answers
6k views

Doing an rm -rf on a massive directory tree takes hours

We're using rsnapshot for backups. It keeps lots of snapshots of the backuped up file, but it does delete old ones. This is good. However it's taking about 7 hours to do a rm -rf on a massive ...
12
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6answers
3k views

Is btrfs production ready?

I've seen a lot of information on btrfs lately. I have been considering ext4 for my next filesystem, but am tempted by btrfs instead. How widely used is btrfs? What are the pro's and con's?
10
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6answers
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Debian: Too many open files

I have long running process at Debian. At some point in throw an error "Too many open files". ulimit -a shows open files (-n) 1024 I wish to increase number of open ...
3
votes
3answers
17k views

How do I set up a shared directory on Linux?

I have a linux server I want to use to share files between users in my company. Users will access the machine with sftp or secure shell. Here is what I have: cd /home ls -l drwxrwsr-x 5 userA ...
24
votes
7answers
39k views

df in linux not showing correct free space after file removal

I have file servers which are used to store files. Files might reside there for a week, or for a year. Unfortunately, when I remove files from the server, df command doesnt reflect the freed up space, ...
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2answers
277 views

Transparent compression filesystem in conjunction with ext4

I am trying to test a project that needs compressed storage with use of the ext4 file system since the application I use relies on ext4 features. Are there any production/stable solutions out there ...
8
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6answers
1k views

How do you know who or what is locking a remote file?

I can tell what process is holding a lock using Unlocker. But the problem is that, when there is a lock on a file on a remote machine, Unlocker doesn't show who or what process is locking. Is there ...
2
votes
4answers
3k views

How to find out what files an installer (rpm, deb) created?

I need to find out all the file system modifications an installer did. Most likely the installed package is an rpm or deb, but an app could of course be simply copied over or compiled and installed ...
18
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7answers
18k views

Why can't you fsck a mounted partition?

It's well-known that you should never fsck a mounted partition. I can understand how this could easily lead to corruption if the filesystem is written to by fsck (e.g., the -a option is used), but why ...
6
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1answer
1k views

Does ZFS replace the need for hardware/software RAID?

I want to provide protection against data loss on my servers. Typically, I'd use hardware RAID 1 or 5, but I've been reading up on ZFS. Is it correct that ZFS itself provides RAID 1 or 5 like data ...
5
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2answers
3k views

It is XFS reliable? In case of a power gone off is xfs riskier that ext3 in data corruption/safey?

I have been having some electrical issues,mostly power going out suddenly for a few months,and although ups solve the thing mostly. But still i am worried about filesystem corruption,and data lost. ...
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3answers
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Directory that a user can read, but root can't?

There's a directory underneath my homedir called ".gvfs". As my regular user account, I can read it just fine: ~ $ ls -lart ~raldi/.gvfs total 4 dr-x------ 2 raldi raldi 0 2009-05-25 22:17 . ...
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5answers
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Linux truncate file

Here's a simple one. How do I truncate an existing file in linux? That is, how do I empty the contents of the file but keep the file. I can always delete the file then touch it but I was wondering if ...
5
votes
2answers
1k views

Modify XFS filesystem creation parameters during kickstart installation

I'm streamlining the kickstart process for a series of EL6.2 (RHEL, CentOS, SL, etc.) systems. I'd prefer to use XFS over ext4 for the growth/data partition. However, I'd like some control over the ...
3
votes
1answer
324 views

Using amazon S3 as storage for attachments in a web-mail system

I am looking to use S3 as data storage service for a mail system. The idea is to allow users to upload files that serve as attachments to their emails, which are then available to download from the ...
3
votes
3answers
1k views

Linux's best filesystem to work with 10000's of files without overloading the system I/O

It is known that certain AMD64 Linuxes are subject of being unresponsive under heavy disk I/O (see Gentoo forums: AMD64 system slow/unresponsive during disk access (Part 2)), unfortunately have such ...
2
votes
4answers
2k views

multiple file systems for mysql

Does mysql support multiple file systems for a single database with most of the tables being on MyISAM? Context: we have a 1.5TB mysql database, which is increasing at the rate of 200GB per month. ...
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2answers
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Resize2fs at 81h and counting

Setup: 12x 1TB drives in a RAID6 (MDADM) crypt-setup running ontop of MDADM LVM running on the crypted drives EXT4 on the LVM Background: I added a new drive to the RAID (increasing from 11 to 12 ...
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4answers
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Sharing filesystem between Linux and Windows servers

What is the best way to share filesystem between Linux and Windows servers via SAN? We have frontend RHEL Linux servers and backend Windows 2k3 servers that pass files via database that is not a best ...
0
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1answer
439 views

file system is going into read only mode frequently

My server file system is going into read only mode frequently. If I reboot my system, It is performing a fsck operation on disks. But, It is exited with exit status 4 ( File system errors left ...
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votes
2answers
974 views

Do partitions needed to be unmounted when resizing a partition?

I have this article http://www.centos.org/docs/5/html/5.2/Deployment_Guide/s2-disk-storage-parted-resize-part.html which is not clear to me. And also someone told me that swap space does not need to ...
32
votes
11answers
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ZFS vs XFS

We're considering building a ~16TB storage server. At the moment, we're considering both ZFS and XFS as filesystem. What are the advantages, disadvantages? What do we have to look for? Is there a ...
44
votes
3answers
5k views

What is the difference between a soft (symbolic) link and a hard link?

I hear that you can now create soft links in Vista too. So, what is the difference between a soft (symbolic) link and a hard link on UNIX/Linux/Vista? Are there advantages of using one over the ...
16
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10answers
9k views

Distributed Storage Filesystem - Which one/Is there a ready to use product?

With Hadoop and CouchDB all over in Blogs and related news what's a distributed-fault-tolerant storage (engine) that actually works. CouchDB doesn't actually have any distribution features built-in, ...
35
votes
4answers
17k views

Drawbacks of mounting a filesystem with noatime?

Having every file be updated just when accessing them sounds like a waste. What's the catch with mounting a file system with the noatime option. What kind of applications/servers relies on the access ...
29
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6answers
3k views

What are .DS_Store files and why does OSX leave them on Windows shares?

Whenever I access windows shares from OSX 10.5 it leaves .DS_Store files on the remote filesystem. What are they used for, and are they necessary, and can they be prevented from being created?
9
votes
4answers
7k views

Need to fix file permissions in a user's home directory

Does anyone have a tool or script that will recursively correct the file permissions on a directory? On an Ubuntu Linux machine, a bunch of files were copied to a USB disk with full 777 permissions ...
7
votes
3answers
5k views

How to corrupt a file system

I am going to be testing 'xfs_repair' on some large file systems ( around 50 TB ) as in the past the memory usage is high. While I could test the program only on file systems which were correct it ...
16
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2answers
6k views

Production-ready, highly reliable filesystems on Linux: ext4 ext3 XFS or JFS (or ZFS)?

The last real question I've seen on this topic is from about two years ago (is ext4 ready for production usage). In the intervening time, how has ext4 improved? XFS, JFS, and ext3 are the standby ...
25
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6answers
13k views

filesystem for millions of small files

Which Linux filesystem would you choose for best speed in the following scenario: a hundred million files ~2k file size in average >95% read access pretty random access high concurrency (>100 ...
17
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2answers
12k views

What is the sticky bit in UNIX file systems? When is it used?

What is the sticky bit in a UNIX file system? As an admin when and how would you use it?
14
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13answers
216k views

Error 0x80070570: How to delete corrupted and unreadable file?

On my system partition I have a folder which cannot be deleted. This folder has been created by restoring files from an Acronis TrueImage backup. The error message says: Error 0x80070570: The ...
25
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3answers
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The XFS filesystem is broken in RHEL/CentOS 6.x - What can I do about it?

Recent versions of RHEL/CentOS (EL6) brought some interesting changes to the XFS filesystem I've depended on heavily for over a decade. I spent part of last summer chasing down an XFS sparse file ...
16
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6answers
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How do I determine the block size of an ext3 partition on Linux?

How do I determine the block size of an ext3 partition on Linux?
8
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6answers
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What's the fastest filesystem for developer builds?

I'm putting together a Linux box that will act as a continuous integration build server; we'll mostly build Java stuff, but I think this question applies to any compiled language. What filesystem and ...
8
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9answers
9k views

How to solve linux subdirectories number limit?

I have a website which will store user profile images. Each image is stored in a directory (Linux) specific to the user. Currently I have a customer base of 30+, which means I will have 30+ folders. ...