103
votes
Accepted
Is there a way to make ext-filesystems use less space for themselves in Linux?
By default, ext2 and its successors reserve 5% of the filesystem for use by the root user. This reduces fragmentation, and makes it less likely that the administrator or any root-owned daemons will be ...
- 445k
39
votes
How to read ext4 partitions on Windows?
WSL2 on Windows 10 Build 20211
Windows allows now to mount physical disks using the Windows Subsystem for Linux 2 (WSL).
However, there is a limitation with this approach as noted in the Microsoft ...
36
votes
Is it safe to use a HDD while rsync is running?
As others have already pointed out, it is safe to read from the source disk, or use the target disk outside out the target directory, while rsync is running. It is also safe to read within the target ...
- 29.3k
31
votes
Accepted
Forcing ext4lazyinit to finish its thing?
In order to 'force' ext4lazyinit to finish the thing it does with maximum priority, you need to mount the filesystem with 'init_itable=0'. By default it is 10 (for detail please see link below)
...
- 426
22
votes
Is it safe to use a HDD while rsync is running?
This depends of the backup system you use, but in general it is a bad idea to modify the contents of a device while you're backing it up. However, you can read its contents; that's a safe operation, ...
- 4,014
16
votes
Accepted
Linux ext4 restore file and directory access rights after bad backup/restore
The standard recommended solution is straight-forward:
find . -type d -exec chmod 0755 "{}" \+
find . -type f -exec chmod 0644 "{}" \+
This will append as many filenames as possible as arguments to ...
- 445k
15
votes
Is it safe to use a HDD while rsync is running?
It is safe to read data from the source areas while rsync is operating, but if you update anything the copy that rsync creates/updates is likely to be inconsistent:
If you update a file that rsync ...
- 23.4k
11
votes
Is it safe to use a HDD while rsync is running?
Source HDD can read anything while rsync.
Source HDD can write any content not related to the rsync content.
Destination HDD can read anything while rsync.
Destination HDD can write anything while ...
- 9,858
10
votes
Linux ext4 restore file and directory access rights after bad backup/restore
I benchmarked sitaram's answer, Peter Cordes's comment, Fanatique's answer, and harrymc's answer, but this answer has the fastest way.
Averages:
Deltik's answer* – 7.480 seconds
* Credit to Peter ...
- 19.2k
9
votes
Parted has no 'resize' command available
Most modern OSes now include the CHUI version of parted 3.2 which has resizepart instead:
(parted) resizepart 2 100%
You should find it in your package manager.
- 212
9
votes
Convert NTFS partition to ext4 - How to copy the data?
1. FreeFileSync GUI tool (Windows, Mac, Linux)
To ensure you don't miss any data, I highly highly recommend using a good file-copy tool like FreeFileSync. It is graphical, no cost, free and open ...
- 1,696
6
votes
How to mount ext4 fs with block size of 65536?
AFAIK ext2/3/4 is based on the generic Linux VFS framework which requires block size to be less than or equal to page size
You may experience mounting problems if block size is greater than page size ...
- 25.5k
6
votes
Accepted
Harddisks aren't recognized in new system (ubuntu 14)
Your disks are fine and are being recognized fine.
Your partitions aren't being recognized because the sector sizes are incompatible. The maximum disk size supported by standard 512-byte sectors on ...
- 6,581
6
votes
Accepted
Cannot delete directory on Ubuntu 14.04.3 LTS
To combine both answers:
check if the parent directory webapps has the i or a attributes set by
lsattr | grep webapps
Then, remove them via
chattr -i -a webapps
- 508
6
votes
Accepted
Optimizing file system for lots of small files?
The smaller the block size (1024 bytes, p.e.), the better for efficient disk usage, in case there's a lot of small files on that partition. Try to reformat that partition with the smallest block size:
...
- 212
6
votes
Accepted
Paragon ExtFS can't write files to Ext4 drive from Windows 10
I solved it as follows:
I uninstalled all 3rd party software like Ext2Fsd, ext2explore, etc.
I cleaned the registry, restarted and paragon extfs is now working. It's copying files to Linux HDD at ...
5
votes
Accepted
partition being mounted as noexec, not fstab, what else can it be?
The default is indeed exec, but using the user option implies the following options:
noexec
nosuid
nodev
As explained in man mount:
user Allow an ordinary user to mount the filesystem. The ...
- 5,509
5
votes
Accepted
How to intentionally corrupt an ext4 filesystem?
Do you want to be able to recover? Or how corrupt are we talking?
I would use dd, a block transfer utility.
dd if=/dev/urandom of=/dev/sdWV count=X bs=Y seek=Z
where
sdWV is the device you wish to ...
- 2,019
5
votes
Accepted
Linux Ext4 Filesystem Explanation Needed, 19 million One byte files equals 80+GB?
I'm not an expert on ext4 but like most file systems it allocates space for files in blocks. The default block size for ext4 is 4096 bytes, so each of your one byte files actually uses 4096 bytes on ...
- 1,135
5
votes
How to create a diskimage of an SD card with partitions having different filesystems?
Linux dd.
dd if=/dev/sdX# of=/home/duckqueen/Desktop/usbimage.iso
- 278
5
votes
Is there a way to make ext-filesystems use less space for themselves in Linux?
Another point which has not been talked about yet is the number of inodes you reserve on your file system.
Per default, mkfs creates a number of inodes which should make it possible to put a whole ...
- 1,439
5
votes
Getting an “is not a block special device.” error when trying to mount an 8TB disk in CentOS 7.6
My guess is you had created a regular file there somehow (or maybe a symlink to such file). Check it. If it was a block device then in the output of
ls -l /dev/sdc1
the first letter would be b; ...
- 67.7k
5
votes
Accepted
How safe is forward compatibility in EXT4?
There are two separate compatibility checks; one is by the kernel, and the other is by the e2fsprogs utilities. The 3.16 kernel supports Metadata Checksums, so there was no problem mounting it. ...
- 786
5
votes
Accepted
Will long time ext4lazyinit damage the drive? Why initializing inode tables in ext4 (no need any kinda init in NTFS)? etc
Strictly speaking, lazyinit is not necessary so long as we never need to try to do certain extreme file system corruption repairs. The problem is if a pre-existing file system is reformatted using ...
- 786
4
votes
How to read ext4 partitions on Windows?
Ext2Fsd was common in the past, but it's usually outdated and constantly broken in newer Windows in my experience. You can also see that in many comments. There's a fork of it called Ext4Fsd
This is ...
4
votes
Is there anything faster than `find . | wc -l` to count files in a directory?
I have written ffcnt for exactly that purpose. It retrieves the physical offset of directories themselves with the fiemap ioctl and then scheduling the directory traversal in multiple sequential ...
- 475
4
votes
Using MySQL and LxD over Btrfs
Fragmentation is a largely unavoidable side effect of a file system being designed with copy-on-write. It's also what allows the nearly free file system snapshots in the first place.
The reason for ...
- 29.3k
4
votes
Quickly removing a gigantic directory on Linux on Ext3/4 drive
The ext3/4 directory isn't a hash table per-se. It's actually a hash tree. That is, the filename is hashed, and the hash is used as an index to insert into a b+ tree. The fastest way to delete ...
- 786
4
votes
Is there a way to make ext-filesystems use less space for themselves in Linux?
if the data you intend to store on it is compressible, btrfs mounted with compress=zstd (or compress-force=zstd) would probbaly use significantly less disk space than ext*
this will make btrfs ...
- 1,007
Only top scored, non community-wiki answers of a minimum length are eligible