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

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Linux: Why change inode size?

Tune2fs allows to change inode size from default (128 bytes on ext3, 256 bytes on ext4) to almost anything, but it should be power of two. What are the reasons for changing default inode size? Here ...
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1answer
280 views

How i can restrict certain file extension upload via ssh?

How can I restrict certain file extensions and file upload size via SSH? I am using Ubuntu 12.10 default installation and Open-ssh server.
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0answers
25 views

Ubuntu 14.04 Desktop as local server - ext4-fs error

I have set an Ubuntu 14.04 as a local server. Also I have two identical hdds on RAID1, on md0. I have tested raid configuration and works ok. I installed virtualbox from the official website and keep ...
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0answers
25 views

How to best use rsync to copy files from ext4 server to btrfs server? [closed]

I am doing daily syncs of a SAMBA AD server that will soon be disabled. Recently I've converted the new server file system from ext4 to btrfs (too many duplicated files was one of the reasons). I have ...
0
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1answer
438 views

centos 6.3 increase disk size on /

I have a VM running CentOS 6.3. LVM is not installed. From the VM side, I have increased the underlying disk from 15GB to 40GB, so I now need to expand the partition and file system. I've managed to ...
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4answers
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Slow ext4 fsck

Why fsck is so slow on ext4 filesystem? I was always using reiserfs or xfs and with those systems fsck was really fast, just few seconds. Now i decided to give a try ext4 but i'm dissapointed that ...
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4answers
672 views

Ensuring a repeatable directory ordering in linux

I run a hosted continuous integration company, and we run our customers' code on Linux. Each time we run the code, we run it in a separate virtual machine. A frequent problem that arises is that a ...
0
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0answers
76 views

Resizing a software RAID remotely, no LVM, / partition

I have a server that has a software RAID without LVM. That is only mdadm. There are the partitions /dev/sda2 and /dev/sdb2 which form /dev/md2. There is also a lot of space after both /dev/sda2 and ...
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3answers
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Possible to mount an ext4 partition image via FUSE?

I'm attempting to mount an ext4 partition image in userspace. (no sudo, no special config/permissions modification to /dev/loop0 or /etc/fstab etc). So I'm hoping FUSE will come to the rescue. ...
0
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1answer
61 views

EXT4 Single Larger Volume or Many Smaller Volumes

My question is regarding the file system performance of EXT4 volumes relative to size. We have a NAS running any arbitrary Linux platform. The NAS has (12) 4TB disks in a hardware RAID 6 with LVM ...
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0answers
9 views

find space used by journal files

Is there any way to find the disk space used by journal. Running xfs on host and ext4 on guest. How can we see the space occupied by journals of these filesystem.is it possible.
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0answers
166 views

Permission denied to resize filesystem

Im attempting to resize a filesystem on a mulipathed volume that I've grown, rescanned all the disks, and resized the multipath map. # resize2fs /dev/mapper/my_vol resize2fs 1.43-WIP (20-Jun-2013) ...
0
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1answer
363 views

existing files are “invisible” to some applications

I have a problem with accessing files on an ext4 file system mounted as type NFS on a Linux server running CENTOS 6.5. I know the files exist on this file system because I can see them when I ...
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0answers
21 views

AWS volume from snapshot missing data

This is a weird one. On a new ec2 instance + new data volume attached at /dev/xvdb mounted with: mkfs -t ext4 /dev/xvdb mkdir /mnt/xvdb mount -t ext4 /dev/xvdb /mnt/xvdb I take a snapshot of ...
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0answers
11 views

use ext3 with inode size 128 and acl

i saw this in one of the docs that i had read Inode size: The default inode size is 256 bytes. Specify a value in bytes that is a power of 2 and equal to 128 or larger in bytes and up to the block ...
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1answer
22 views

Is it possible to update stripe-width on an existing, and used, ext4 fs?

I have a RAID 5 with 5 3TB drives (8 in few weeks), on a Debian. There is only one ext4 partition on it, using all the space available. Actually, due to origins of the RAID (4 drives), the ext4 fs ...
0
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1answer
49 views

Is my default File System ext4

By running df -hT that shows mounted file systems, how can I know if my default FS is ext4? Also as mentioned by one of the MongoDB engineers in this video (@1:13) from M202: MONGODB ADVANCED ...
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1answer
102 views

Warning :mounting fs with errors, running e2fsck is recommended

Linux server will hang and when I restart it will take around 2 hours to come up and resume normal operations. I checked the system log files and found mounting fs with errors, running e2fsck is ...
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2answers
994 views

Testdisk won’t list files for an ext4 partition inside a LVM inside a LUKS partition

I have accidentally deleted a file that I want to recover. The partition is an ext4 partition inside an LVM partition that is encrypted with dm-crypt/LUKS. The encrypted LUKS partition is: /dev/sda2 ...
0
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1answer
52 views

LVM on disk with no partition table. How to reallocate free space with fdisk?

I shrank an LVM in half using these commands: e2fsck -f /dev/VG/LV resize2fs /dev/VG/LV 5G lvreduce -L 5G /dev/VG/LV Inspecting the physical volume yields this: --- Physical volume --- PV Name ...
4
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5answers
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How to extend an ext4 partition and filesystem?

I have a 400GB disk with a 320GB ext4 partition. I would like to grow the ext4 partition to use the left space (80GB of free space). +--------------------------------+--------+ | ext4 ...
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4answers
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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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5answers
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EXT4 “No space left on device (28)” incorrect

I have been through the other questions/answers regarding inode usage, mounting issues and others but none of those questions seem to apply... df -h /dev/sdd1 931G 100G 785G 12% ...
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7answers
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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?
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1answer
210 views

Software-RAID with ext4 but without 64bit support

last year I set up a Software-RAID5 with 5x3TB yielding 12TB of usable capacity. Just today, needing more storage, I have finished growing the RAID to two more 3TB disks: Personalities : [linear] ...
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4answers
6k views

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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0answers
429 views

Failing to mount root from ramdisk while PXE boot

I have a working TFTP/DHCP PXE boot environment where I've already booted some images successful. Now I built an CentOS 6.5 diskless image and this one is failing booting with the following error: No ...
5
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3answers
519 views

How to recover data from a messed up drive (LVM written on top of Ext4)?

The previous administrator of a server that is now under my supervision made a mistake. He accidentally created a LVM volume (no more than pvcreate, I think, though not sure) on a disk that actually ...
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1answer
2k views

Can I lvreduce after lvextend without losing the ext4 partition inside it?

In a botched attempt to move my root partition from one disk to another I have done the following: added new disk partitioned it with parted (part #3 is now almost totally filling the disk) ...
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2answers
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No posix acl in debian Wheezy with ext4

I was running a new script and encountered the following error: Your filesystem or build does not support posix ACLs So I thought no problem, just add acl,user_xattr to my fstab. It now looks ...
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Slow ext4 read performance on 24-drive hardware RAID6

I have a RAID6 configuration spanned over 24 drives (12x directly attached to the RAID card, 12x via external SAS) running on an ARECA ARC-1880IX-12 (fw V1.51 2012-07-04). The RAID makes up one single ...
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3answers
38 views

How can I modify the wtime of ext filesystem

How can I modify the superblock of an ext filesystem so that I can set the field wtime (Last write time)? I've tried with debugfs: debugfs 1.42.9 (4-Feb-2014) debugfs: open /dev/sdd2 -w debugfs: ...
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1answer
2k views

Centos 5.5 [Read-only file system] issue after rebooting [closed]

I have a virtual server under centos 5.5 (hosted by a japanese company called sakura ) Since yesterday, connection through ssh couldn't be established. I've contacted support center who told me to ...
0
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2answers
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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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1answer
67 views

First 500MB of RAID6 array is wiped, how to recover?

We have a RAID6 array with 12 disks on a 3ware 9650SE-12ML controller. An engineer of our server provider issued this command by mistake: sudo dd if=/dev/zero of=/dev/sde bs=1M count=500; sync; ...
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2answers
4k 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 ...
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1answer
87 views

impossible creating a ext4 fs with block size of 1024

Im triying to build up a new server for a service that saves the data on very small files of max 1 kb on the fs. The problem its, now we are using a block size of 4 kb and we are wasting a lot of ...
5
votes
3answers
6k views

df reports wrong free space for an Ext4 partition

My system is CentOS 6 x86_64 with root partition formatted as ext4. df reports around 3Gb as used space: Filesystem 1K-blocks Used Available Use% Mounted on /dev/md1 ...
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2answers
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Ext4 self errors after some time on CentOS 5.8 64-bit

I get such warnings in dmesg: EXT4-fs error (device md2): mb_free_blocks: double-free of inode 0's block 602619328(bit 15808 in group EXT4-fs error (device md2): mb_free_blocks: double-free of inode ...
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0answers
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Linux filesystem ext4 fragmentation

I have a question about the filesystem ext4 and disk fragmentation: Does ext4 place files in the same directory near or next to each other on the disk? And if so how is it fragmented, for example is ...
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1answer
147 views

How can I grow an ext4 filesystem inside a dm-crypt/LVM volume?

I have a disk with this format: sdc 8:32 0 1,8T 0 disk └─sdc1 8:33 0 1,8T 0 part ├─vg-lv1 (dm-0) 254:0 0 900G 0 lvm ...
3
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0answers
267 views

Cannot set ACL on ACL-enabled EXT4 partition

I am trying to enable xattrs and acls on a Debian machine. I've (re)mounted the partition in question with user_xattr and acl. (/dev/md3 is the partition in question) root@fs01:/# mount | grep ...
2
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3answers
8k views

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
695 views

Remount root RW without reboot

Today I did something stupid on production xen vm server. I mounted the external device mapper as read only to make a copy of the filesystem. This process went well but then the rootfs / become ...
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0answers
134 views

Replacing files with symlinks takes more space - Fedora19 EXT4

Background: We are using PHP CacheLite. In order to have a human readable path to cache files cache_{hash}_{hash}, there is a symbolic link that is more descriptive of the cache contents. We ...
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3answers
4k views

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 ...
0
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1answer
203 views

fsck ext4 inode error

Today while I was booting I got an error in an ext4 partition with some inodes. I just entered the root password and run fsck manually but I am a bit worried. fsck warned many times about some errors ...
2
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1answer
102 views

How do I replace the root filesystem (ext4) with a new one in LVM with one which has more inodes?

I have a few systems which have been running over a decade in a cluster on SLES 10 (now long past EOL). We're migrating to CentOS 6 64-bit. I got everything done but the final data syncs, and lo and ...
0
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1answer
289 views

How do I allow users to add/modify files in a directory but not change the directory - Linux

How can I modify a directory so that it is owned by a group and users in that group can add and delete files and create sub directories but are unable to change the permissions on the parent ...
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1answer
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Loss of data when trying to fix ext4 “group descriptors corrupted!”

When I try to mount an existing disk, I get the message sudo mount -t ext4 /dev/sdc1 /data mount: wrong fs type, bad option, bad superblock on /dev/sdc1, missing codepage or helper program, ...