The ext4 or fourth extended filesystem is a journaling file system for linux/*nix developed as the successor to ext3.

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Storing and backing up 10 million files on Linux

I run a website where about 10 million files (book covers) are stored in 3 levels of subdirectories, ranging [0-f]: 0/0/0/ 0/0/1/ ... f/f/f/ This leads to around 2400 files per directory, which is ...
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Recover ext4 file

How to recover recently deleted file from ex4 partition? Mashine hosts Open SUSE 11.2 (kernel 2.6.31)
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How do I find a file on Linux in an ext4 filesystem that's being written to frequently?

I've got a Ubuntu system which is writing a block to disk every 1-2 seconds. Some kind of log accruing an error. How do I find which file it is? I've been poring over lsof output and tailing ...
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Ext4 superblock corrupted after successful(?) mdadm grow and resize2fs

Some system details AMD Phenom II X6 1090T, 16GB DDR3 1600 running 11.04 natty, 2.6.38-8-server Raid in question consists of 5 SATA drives; 4 Samsung, 1 Western Digital; 500 GB each Drives are ...
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1answer
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[Fedora 14][LVM2&EXT4] Overwritten partition config

Accidentally, I deleted my '/etc' & '/bin' folder (I know, my fault). Then, I boot liveCD and tried to copy or fix this issue. And then when I can't figure nothing to fix it, I don't know why, I ...
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how to make ext4 more reliable? [closed]

As ext4 introduced more reliability than ext3 with block journals, is there any chance to suppose it 100% reliable? What if enabling block journaling on it, which is disabled by default? I have an ...
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Ext4 partition bigger than 2TB?

Is there a way to make partition bigger than 2 TB on ext4 file system ?? Im trying to do that on debian but get message Partition size can not exceed 2TB ...
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On linux, what does it mean when a directory has size 0 instead of 4096?

Here's a strange thing I haven't seen before -- a directory whose size is reported by ls as 0 instead of 4096, and I can't create any files within it. # ls -ld lib home drwxr-xr-x. 2 root root 0 ...
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1answer
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25TiB for /home from 16TiB, what to do with ext3?

I have recently lvextend my logical volume (where /home is) from 16TiB to 25TiB. However, when I try to run extend2fs on my /dev/vtrak/home, it complains that resize2fs 1.41.12 (17-May-2010) ...
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SSD TRIM (discard) problems with ext4 on Crucial C300 SSDs with CentOS 5.5

Playing around with using a modern kernel (2.6.37 currently) on an older OS (CentOS 5.5) so we can get TRIM (discard) working on our SSDs (Crucial C300s). The most recent hdparm (9.37) concurs that ...
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Partitioning an External HDD

I have an external hdd and i want to partion it into 2 partitions which are ext4 and ntfs. Is that OK with this kind of partitioning and Is there a problem with partitioning an external hdd rather ...
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1answer
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Mystery stack traces in /var/log/messages

I am seeing the following messages in my server's /var/log/messages. They look like stack traces and are not preceded by any narrative (e.g. "such-and-such has gone wrong"). I am almost certain they ...
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Can't fsck From Live CD

I'm trying to run fsck from a Linux Mint Julia live CD, but something seems to be going wrong. When I run: sudo fsck /dev/sda5 I get the response fsck from util-linux-ng 2.17.2 e2fsck 1.41.12 ...
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1answer
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Is it really necessary to call /bin/sync twice before an unmanaged power-off?

My company sells an "embedded device" which is implemented as a headless Linux box with ext4 on an internal SSD. Some of our users have a habit of doing a "save current settings" on this box, and ...
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2answers
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Is data=journal on a separate device on Ext4 as good as using a RAID controller with battery backed cache for file system consistency?

It seems to me that data=journal prevents file system inconsistency in the case of power failure. Using it with a dedicated journal device mitigates the performance penalty of writing the data twice. ...
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3answers
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Files on ext4 on Drobo with corrupt, zero-ed out blocks

I have a 2TB ext4 file system (Ubuntu running Linux kernel 2.6.31-22-server x86_64). This file system is the second drive on a Drobo box plugged in via USB. We've not had problems on the first drive ...
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2answers
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Can't Mount Remote Share From RHEL 6

I'm trying to upgrade some Linux systems to RHEL 6, but I cannot mount the home directories. I'm using EXT4 for the RHEL 6 system and EXT3 on the RHEL 5 server, which I'm mounting the directory from. ...
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1answer
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Can't configure quota on CentOS 5.5. Strange behaviour of quotacheck and other quota commands

I have Centos 5.5 linux with quota enabled in fstab [root@drone3 ~]# mount | grep usrquota /dev/sda4 on /storage type ext4 (rw,noatime,nodiratime,usrquota) When I tray to activate quota on ...
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Causes of sudden massive filesystem damage? (“root inode is not a directory”) [closed]

I have a laptop running Maverick (very happily until yesterday), with a Patriot Torx SSD; LUKS encryption of the whole partition; one lvm physical volume on top of that; then home and root in ext4 ...
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4answers
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exportfs: Warning: /home/user/share does not support NFS export

'exportfs -r' returns me this error when I'm trying to export /home/user/share (ext4): exportfs: Warning: /home/user/share does not support NFS export. /etc/exports: /home/user/share ...
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2answers
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mdadm lvm and ext4 slowness - How can I speed it up?

I can't figure out why I'm getting such terrible times out of my mdadm and in particular the lvm partitions in it. I made the raid: mdadm --create --verbose /dev/md0 --level=5 --chunk=1024 ...
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1answer
261 views

Mac Fonts stored on Ext (Linux File System)

I currently have a PowerPC g5 running Mac OSx. I've network shared one of the external hard drives (which is mac formatted, hfs+ journalled i believe). I'm now upgrading this to an ubuntu computer, ...
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Ubuntu 10.10 Maverick Server makes system locks up at random intervals (i7 930; 12GB RAM)

To introduce: I have a machine with the following specs: Intel Core i7 930 12GB Ram Corsair 2xSamsung HDD 320gb (No Raid, just partitions) Asus P6TD Deluxe The machine has been at Datacenter just ...
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Should use EXT4 or XFS to be able to 'sync'/backup to S3?

It's my first message here, so bear with me... (I have already checked quite a few of the "Related Questions" suggested by the editor) Here's the setup, a brand new dedicated server (8GB RAM, ...
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Mount a ext4 partition on Mac OS X

Is it possible to mount a Linux ext4 partition on Mac OS X? Please describe the procedure - risk free - thanks. Edit Aug 2012 The best solution I found was to use a 2nd machine with Linux, mount ...
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1answer
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Does increasing the journal size improve performance for ext4 filesystems?

There is an article on linux-mag which says that increasing the size of the journal on ext4 filesystems actually improves filesystem performance for very large partitions. I'm wondering if anyone ...
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1answer
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Does anybody have experience with Dump(8) and the ext4 fs

I have done some research online and some people claim dump/restore have good ext4 support and others claim the system is broken and restores come back corrupt. My question is, do they work well ...
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1answer
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How can I disable ext4 has_journal option on dedicated server?

I have Ubuntu 10.04 dedicated server with SSD drive. Hence I want to disable the file system journal. Normally this can be done like this "tune2fs -O ^has_journal /dev/md2". However the root file ...
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1answer
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How to make partition, raid5 and filesystem on 6x2TB WDC-drives in Linux

I'm getting confused by this "Advanced Format" (4KB sectors) talk of bigger (2TB) drives - and I am wondering about how I would resolve this if I'm building a new software (mdadm) RAID-5 array. The ...
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2answers
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How to check (fsck) a filesystem on a md device (linux/mdadm)

I have a partition lying on a software raid device, /dev/md4 On boot, fsck fails and the partiton cannot be mounted. Trying to fsck manually, I get an error: sudo fsck /dev/md4 fsck from ...
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1answer
638 views

Why does this loopback device creation malfunction?

The stackoverflow people thought this was more appropriate here, I put it there as it is part of a program but I can see their POV, so here it is: At the bottom of the code you can see it failing. In ...
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Ext4 corrupted after RAID failure and fsck taking too long to run

I am completely lost :( I got software RAID10 with 4 drives, one of them failed yesterday, right before or after the failure system crashed and restarted. It started data rebalancing and completed it ...
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1answer
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Unable to write to root partition

For some reason, we are unable to write to my root ext4 partition. Unfortunately I don't have physical access to the computer, and I can't reboot or do anything because it's read only? How can we fix ...
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Failed MDADM Array With Ext.4 Partition - “e2fsck: unable to set superblock flags on /dev/md0”

Had a power failure and now my mdadm array is having problems. sudo mdadm -D /dev/md0 [hodge@hodge-fs ~]$ sudo mdadm -D /dev/md0 /dev/md0: Version : 0.90 Creation Time : Sun ...
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Questions for Ext3/4 Features ( dir_index,filetype) and XFS File system Performance

I am developing an applications which reads huge list of directories and check file types using file command and using ext4 file system. When i look into Ext4 , i see it have two interesting features ...
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1answer
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Restoring data from corrupted ext4 partition under LVM - fsck or repair bad blocks first?

I am using Linux on my notebook. My notebook recently fall on ground and now I am trying to save as much data from my damaged hdd as possible. I can boot notebook from Linux live CD. Long story ...
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Can I unformat an NTFS volume that was formatted as ext4?

No data was written to it. Is there a tool that will allow me to do it? I would prefer a free tool, but please recommend non-free if only such software can do the job.
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Ubuntu 10.04 with ext4 gets repeated IO errors

we installed a new DELL server with the (not supported) Ubuntu 10.04 LTS. We configured a hardware RAID (I think RAID 1) with the DELL tools before installing Ubuntu. The server is not under load at ...
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ext4 fs breaking after power outages

I am experiencing quite a typical but strange problem: the hdd is going bust after power cuts on my server. I can feel it huge work done by fsck on startup after the crash, and then my subversion ...
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3answers
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changing filesystem format from xfs to ext4 without losing data

I have a fresh Lucid Lynx (Ubuntu 10.04) running on a laptop. where I defined the filesystems as: mount point / on ext4 (46 Gb) mount point /home on jfs (63 GB) swap as 3 Gb I left the machine ...
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1answer
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Where to get comprehensive list of tune2fs/tune4fs options per filesystem?

tune4fs can use many undocumented (I mean they are not yet in man tune4fs) options for ext4 filesystem. For example, huge_file, flex_bg, dir_nlink, extra_isize and some others. Is there a ...
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Linux: Why change inode size?

Tune2fs allows to change inode size from default 128 bytes to almost anything, but it should be power of two. What are the reasons for changing default inode size? Here it's written that this can be ...
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CentOS 5.5 ext4 conversion problem - ext4 partition is recognized as ext3

I had 5.4 machine. Upgraded to 5.5 today via yum upgrade. All went fine. Rebooted. Wanted to convert root partition to ext4 (I have three partitions: /boot, / and swap). All of them on software RAID 1 ...
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Running resize2fs on /

I'm trying to resize an ext4 filesystem on a Fedora 11 box. Using fsdisk and lvm, I was able to grow the partition and logical volume containing the filesystem. When I try to run resize2fs on the ...
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Immutable hard links on ext3/4?

In my research on file versioning at the fs level, snapshotting, and related ideas, I took a look at hard-links and exactly what they are and how they behave. Using rsync you can get a pretty slick ...
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Best way to 'harden' embedded ext4 file server against unexpected loss of power?

First, a little background: my company makes an audio streaming device that is a headless, rack-mounted Linux box with a Solid State e-SATA drive attached. The drive is formatted with ext4. The ...
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2answers
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What are the merits of ext3 over ext4?

Specifically want to use the storage for music/video files but with a smattering of usual doc/xls/etc) - wondering if there is a concrete reason to go for one over the other. Thanks
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Which “features” of ext4 existing ext4 partition uses?

When I create ext4 filesystem, there are many "features", which I can enable and disable - like has_journal, extent, huge_file and so on. Is there any way to know, which options were used while ...
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ext4 in debian 5 (2.6.26)

Is ext4 ready for production usage in debian 5 (with linux kernel version 2.6.26) ? Will it be stable, oops-free and bug-free?
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What is the maximum number of files a file system can contain?

Given the current structure of a directory entry on a ext4 file system on Ubuntu, what is the maximum number of files a file system can contain? What is the general method of calculating the maximum ...