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Questions tagged [filesystems]

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.

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. A file system organizes data in an efficient manner and is tuned to the specific characteristics of the device. A tight coupling usually exists between the operating system and the file system. Some file systems provide mechanisms to control access to the data and metadata. Ensuring reliability is a major responsibility of a file system. Some file systems allow multiple programs to update the same file at nearly the same time.

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.nfsXXXX files appearing, what are those?

I have an application running (on RHEL5) that streams data onto an NFS share. Recently, I saw a lot of .nfsXXXX... (xxx being a hexadecimal number) appearing in its working directory, where the application writes hourly files and later moves them to…
nos
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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 number of files a file system can contain?
user32678
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Removing an (apparently) infinitely recursive folder

Somehow, one of our old Server 2008 (not R2) boxes has developed a seemingly infinitely-recursing folder. This is playing havock with our backups, as the backup agent tries to recurse down into the folder and never returns. The folder structure…
KenD
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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 can't read-only checks be run on mounted disks?
mike
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What happens if I delete lost+found

When you create some Linux filesystems like ext3 a 'lost+found' directory is created. According to this files will be placed there if files were damaged from some kind of system crash. What happens if this directory is removed, and the system…
Zoredache
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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 94% / # du -hxs / 124G / I read that open but…
Andreas Kuntzagk
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When is fsck dangerous?

Recently I've seen the root filesystem of a machine in a remote datacenter get remounted read-only, as a result of consistency issues. On reboot, this error was shown: UNEXPECTED INCONSISTENCY: RUN fsck MANUALLY (i.e., without -a or -p…
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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 (user, group, other - read, write, execute) in…
mlambie
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Unable to write to disk but disk isn't full

I am using Ubuntu 12.04 and can't write to any file, even as root, or do any other operation that requires writing. Neither can any process that needs to write, so they're all failing. df says I've got plenty of room: Filesystem Size Used…
felwithe
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Mount Docker container contents in host file system

I want to be able to inspect the contents of a Docker container (read-only). An elegant way of doing this would be to mount the container's contents in a directory. I'm talking about mounting the contents of a container on the host, not about…
dflemstr
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Why does deleting a big file take longer?

My understanding is that running rm on a file simply unlinks it, marking the space as free in the filesystem. It should then follow that deleting one file always takes roughly the same amount of time (i.e. delete speed is proportional to number of…
Tom Marthenal
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See what files are being written to (like iotop but for files, not processes)

I have a Linux server, and it's doing a lot of disk io. There is one process that is doing most of the disk writes. I found this out with iotop, which shows the processes that are doing disk I/O. Is there an equivant programme (in the debian lenny…
Amandasaurus
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Does btrfs have an efficient way to compare snapshots?

While diffing mounted snapshots would work, it sounds like it could be horribly slow in many cases. Is there btrfs specific functionality for diffing snapshots? (I was unable to find any in the docs)
Catskul
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How beneficial are self-healing filesystems for general usage?

I have recently looked into advanced filesystems (Btrfs, ZFS) for data redundancy and availability and got interested in the additional functionality they provide, especially their "self-healing" capabilities against data corruption. However, I…
Prototype700
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Copy directory tree without empty directories?

I have the following tree # upper letters = directory # lower letters = files A |-- B |-- C |-- D |-- e <= file |-- F |-- G I need to copy this tree to another destination, recursively ignoring all the empty directories. So the…
Dane O'Connor
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