A filesystem is a way to organize and store computer files with their data.
1
vote
1answer
30 views
What is the sense behind ZFS's limits?
Why does ZFS have the following limits?
What internally limits these things? Why couldn't ZFS have a theoretically unlimited volume size, or filename length, and so on?
2
votes
0answers
10 views
Mounting HPFS partition read/write?
I'm not talking about NTFS partitions that show up as HPFS/NTFS. Is mounting actual HPFS partitions read/write possible?
1
vote
0answers
7 views
BTRFS balance completed, but still shows data stored in “single” mode
I have three drives (8TB, 4TB, 3TB). Originally, I created a btrfs partition on the 8TB drive and copied all my data there. I added the 4TB and 3TB drives by using btrfs device add, and then then ran ...
1
vote
3answers
24 views
Corrupted usb key cannot be mounted or formatted
I have a USB stick that I can't operate on no matter what.
lsbkl -f
shows an empty line and no partitions
NAME FSTYPE LABEL UUID MOUNTPOINT
...
3
votes
2answers
53 views
Why is writing to a existing file faster than write a new empty file?
I use MappedByteBuffer to write file in linux.
File file = new File("testFile");
RandomAccessFile raf = new RandomAccessFile(file, "rw");
FileChannel fc = raf.getChannel();
MappedByteBuffer mbf = fc....
0
votes
0answers
35 views
How to format a 4TB USB external drive to use on LINUX (Ubuntu) and Mac OSX?
I'm having a hard time getting a 4TB external USB drive to work on both LINUX (Ubuntu 14.04) as well as on my Mac OSX.
The problems seem to be with inconsistent ability to read/write the USB drive.
...
1
vote
3answers
23 views
why df get result inconsistent with lsblk?
The output yielded by df consistent with lsblk
debian8@hwy:~$ df -h /dev/sda1
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 47G 34G 14G 72% /media/xp_c
debian8@hwy:~$ df -h ...
0
votes
0answers
40 views
How to Zip the files consuming larger space?
i have tried this code below
du -a $path | sort -n -r | head -n 5 > diskspacefile.txt
file=$(cat diskspacefile.txt)
while read p; do
filesize=echo $p | awk '{print $1 }'
if [ $filesize >...
0
votes
0answers
23 views
Fuse file system with “default permission” option [on hold]
I am new to fuse. I have mounted fuse by the following command.
/mnt/fuse -o default_permissions -o allow_other -o nonempty -o hard_remove –d
Now If I login as "test" user and tried to create a file ...
-1
votes
0answers
33 views
How to create mount point in a filesystem and assign memory to it [on hold]
How to create mount point in a file system and assign memory to it.
I want to create a mount point in a filesystem and add spacee to it.
i need a mount point and directory to be created in a ...
0
votes
3answers
27 views
need information on creating swap memory on unix
I am creating swap file using fallocate -l "$memory" "$swapfilename" command.
I have some questions:
On which file system is the swap file created if multiple file systems are present? Can we ...
0
votes
2answers
28 views
How to recover data after lvremove in centos 7.0?
I did a stupid thing by removing a Logic volume by issuing the below command.
lvremove -f /dev/cl_dhcppc4/home
However, immediately I restored the lvm from the backup file.
vgcfgrestore --file /etc/...
1
vote
2answers
65 views
Move directories despite of errors
When moving a directory to another drive, if there are errors in the process, nothing will be deleted. I am getting this kind of errors:
mv: cannot stat ‘originaldirectory/longpath/irrelevantfile’: ...
1
vote
0answers
14 views
MacOS: USB history (name and timestamp of connected devices)
My external HDD was stolen from me a few weeks ago but I just realised this recently. I really need to know when was the last time I connected this device to my computer. I know it's name, is there ...
1
vote
0answers
22 views
mkdosfs to format dashcam SD card FAT32 with 32kb cluster size
I am trying to write a script to reformat a dashcam SD card, as is recommended by the manufacturer. I can do this on a windows system with a simple python script, a snippet here:
...
fm = windll....
0
votes
0answers
16 views
Centos device /dev/sdb1 is not a valid luks device?
I have Centos on Virtualbox, when I installed Centos I used all 20G. After installation I made extend for more one driver with 5G inside Centos everything is good when I made partitions and file ...
0
votes
0answers
23 views
“Software Error” when trying to delete a (corrupt?) file in mint. Can't see the file, still taking up space [on hold]
My computer recently died in the middle of transferring a ~70gb backup image onto an exfat drive. Plugged the drive into another machine running mint the next day and saw the file was the correct size ...
1
vote
0answers
11 views
Grow an HFS+ Volume on OSX without re-partitioning
I have created a master image using Clonezilla so we can (frequently) re-image a bunch of our machines.
The problem I am having lies in the deployment of the image to machines with larger HDDs. The ...
-2
votes
1answer
50 views
Showing read only /var partition on Debian
I have seen an industrial computer running Debian, to protect the flash disk from writes and have the system in a defined state after every boot, the whole disk was mounted read-only, there are no ...
1
vote
0answers
14 views
Does FUSE have any specific cache interaction?
I'm a bit lost in how kernel caches work in general, so generic cache information is fine too, but I'm specifically working on FUSE.
So, I read that the kernel looks up a file/directory via VFS using ...
0
votes
0answers
10 views
Are dcaches in VFS file-system-specific or not?
Information I found is that file-systems that use inodes and dentries, such as ext2, have inode caches and dentry caches. In addition to that, VFS has its own inodes and dentries along with its own ...
0
votes
3answers
81 views
What is a flat file?
Is it a plain text file or binary file or just character file? Can someone explain what a flat file actually means?
12
votes
1answer
615 views
How many directories can be nested?
I'm curious, how many folders can be nested, and why? Is there a limit?
What I mean by nested is when folders are in this structure:
folder
|_ folder
|_ folder
|_ folder
|...
1
vote
1answer
30 views
open file and current directory permissions
I'm trying to learn about file and directory permissions in unix/linux.
I think I got the general idea, if I want to
cat ~/foo/bar/text.txt
I need x+r permission on ~, ~/foo, ~/foo/bar, and r ...
0
votes
0answers
30 views
When would VFS be required to do a full path walk instead of using the dentry cache?
So, from what I understand, if you have accessed /foo/bar/file, that path is dentry cached. So, you'll be able to access the inode for file without path-walking /, foo, and bar.
What are the ...
2
votes
1answer
37 views
What are the list of different type of caches in Linux file systems?
I've been reading this page, http://www.tldp.org/LDP/tlk/fs/filesystem.html, and I have trouble organizing all the different caches it's talking about. Especially, I don't understand the different ...
1
vote
0answers
10 views
mhddfs filesystem hangs after a while with large directory
I have 2 RAID1 of 4TB each which are joined together with mhddfs. There is one directory that exists on both disks that contains hundreds of thousands of files. There is a lot of read/write happening ...
1
vote
0answers
28 views
Encrypted (luks) + LVM Ubuntu installation where /home is encrypted as well (ecryptfs): How to make a new partition for /home?
I've installed Ubuntu 16.04, encrypted and with LVM. I also chose the option to encrypt /home (which encrypts the directory with eCryptfs).
The default settings make an unencrypted /boot and an ...
0
votes
1answer
15 views
What are the folder that I cannot set as encrypted folders decrypted at login? [closed]
I want maximize the number of folders encrypted with ecryptfs and decrypted at login with the module pam_ecryptfs.so.
Which folders cannot possibly be encrypted before login in?
I guess a lsof ran ...
2
votes
2answers
57 views
How do I find out what filesystem FUSE is using?
when I run mount, I can see my hard drive mount as fuseblk.
/dev/sdb1 on /media/ecarroll/hd type fuseblk (rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096,...
12
votes
2answers
909 views
What exactly is dot dot (..)? Why is its behavior different with symlinks?
I am trying to understand the nature of .. (double dot). It seems to point to different targets depending on how you access it.
Example:-
/outer/
middle/
inner/
inner ...
0
votes
2answers
24 views
Debian gnome-disks and mkfs can not format external hdd
I have an HDD bought a few years I have not touch since at least a year.
When connecting it to my laptop, the drive does not appear in the drive list in the file explorer.
I used fdisk to be sure it ...
0
votes
2answers
64 views
How do commands like ls or stat distinguish the file type?
How do commands like ls or stat distinguish the file type, whether the object is a file or directory?
For example, I created these two objects, considering the fact that a directory is also a file... ...
5
votes
1answer
41 views
How are files/dirs hidden from ls -a while still beeing accessible otherwise in a POSIX compliant system?
So for example in ZFS under FreeBSD and ZoL, there is a magic .zfs dir inside of each zpool mountpoint and you can use zfs set snapdir=visible to make that .zfs dir visible.
What makes me curious is, ...
0
votes
2answers
35 views
Recover specific files from deleted EXT4 partition
Is there any way to recover a few specific files from a deleted EXT4 partition. I deleted all partitions on my 480GB SSD. Afterwards, I created a 200 GB NTFS partition (which is mostly empty) and I ...
0
votes
1answer
18 views
Accessing FAT32 partition from Windows
I'm working on a Raspberry Pi project on a Zero board. I'd be so happy if I could write a sizable number of files from a Windows or MAC laptop onto the microSD card that I plug into my Pi project, and ...
1
vote
1answer
22 views
How to delete a invalid osd in ceph cluster?
[root@dev-master ceph-cluster]# ceph osd tree
ID WEIGHT TYPE NAME UP/DOWN REWEIGHT PRIMARY-AFFINITY
-1 0.01740 root default
-4 0.00580 host osd2
0 0.00580 osd.0 down 0 ...
0
votes
1answer
34 views
Required permission to create directory
I'm trying to create a sub directory under existing directory tree. I want to know if only the permissions of directory where I'll be creating my sub directory matter or the parent directories will ...
1
vote
1answer
14 views
collectd is creating /home folder on my mac and I cannot remove it
I posted this here instead of the apple site because this seems more like a *nix-ish issue and I think this site would be better suited for it.
I had installed collectd with graphite for monitoring ...
-4
votes
2answers
43 views
how to set alias for the folder in Linux [closed]
I want to set the alias for the "abc-abc" folder as "abc" in Linux.Can you help me?
EX: /raj/abc-abc/xyz/data
1
vote
1answer
57 views
Do system calls call themselves?
Do they? for example, I was thinking of the simple system call chown.
Does it call other system calls like read and write? How can we find out?
3
votes
2answers
41 views
Permissions change from mkdir to mount
I am working with LVM and filesystems and I am confused why when I do a mkdir /mntpt and then a mount /mntpt that I am seeing permissions change. It is still a directory is it not?
What is ...
0
votes
1answer
640 views
Cannot remove file: “Structure needs cleaning”
I have an external hard drive which is encrypted via LUKS. It contains an ext4 fs.
I just got an error from rsync for a file which is located on this drive:
rsync: readlink_stat("/home/some/dir/...
0
votes
0answers
13 views
xfs_quota -x -c “report ” $PATH return null when configured project quota
cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Tue Aug 9 15:24:43 2016
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8)...
1
vote
3answers
100 views
What is the purpose/benefit of putting “./” at the begining of a path? [duplicate]
Is there ever a benefit to preceding a path with ./ (dot slash)?
In most cases, cd ./home is equivalent to cd home (and also cd ./././././home). Is there ever a case where these two paths would ...
1
vote
1answer
40 views
harddisks change /dev name while running
I know that the assignment of disks to /dev names can vary at boot, but how the heck can it vary in a session? I'd swear that happened to me yesterday, /dev/sdb and /dev/sdc changed places, and I ...
-1
votes
1answer
29 views
Need of Dentry despite traversal could be done by Inode
In Linux, if we have directories represented as special type of files having entry of each file name it has. Obviously, we could traverse and find out paths, then why do we need Dentries to assist us ...
0
votes
1answer
25 views
Testing password against encrypted ext2 container
I have a encrypted container containing a mountable EXT2 file system with no partition table. How can I mount that file using cryptsetup? My attemps fail with 'VFS: cant find ext4 filesystem'...
11
votes
3answers
1k views
How to merge multiple hard drives?
I have a server with three hard drives:
250 GB
3 TB
250 GB
How can I merge multiple hard drives as one bigger volume of ~ 3.5 TB? I am a programmer not a system administrator.
2
votes
1answer
33 views
How to stop auto mounting of devices in Ubuntu?
I have an Ubuntu 16.04 LTS desktop system that I use to rescue disk drives (using dd or ddrescue). Whenever I plug in a disk drive it is automatically mounted and shown in the file manager.
I don't ...
