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Questions tagged [unionfs]

allows files and directories of separate file systems to be transparently overlaid and forming a single coherent file system

Probably create the new tag and remove and from existing questions?

Wikipedia

UnionFS is a filesystem service for Linux, FreeBSD and NetBSD which implements a union mount for other file systems. It allows files and directories of separate file systems, known as branches, to be transparently overlaid, forming a single coherent file system. Contents of directories which have the same path within the merged branches will be seen together in a single merged directory, within the new, virtual filesystem.

http://en.wikipedia.org/wiki/UnionFS

Another explanation from the kernel documentation would be:

Overlay Filesystem

This document describes a prototype for a new approach to providing overlay-filesystem functionality in Linux (sometimes referred to as union-filesystems). An overlay-filesystem tries to present a filesystem which is the result over overlaying one filesystem on top of the other.

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16 questions
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How do I create an overlayfs on NFS on a diskless device?

Looking for example/howto/etc of howto create an overlayfs for my diskless computers. I have multiple diskless computers that have root on nfs configured. I would like to use an overlay for files that need to be changed for the computes. Like…
Mike
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2 answers

"Unknown filesystem unionfs" although all packages and modules are installed

I'm trying to mount a unionfs file system in fstab (as one of the steps in this guide), with the following line: unionfs /usr unionfs nodev,noatime,dirs=/.filesystems/usr/overlay=ro:/usr=rw 0 0 I've installed the package unionfs-fuse and added…
Tomas Aschan
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2 answers

How do I automount a unionfs-fuse filesystem?

I can run the shell command: unionfs-fuse /changedata=RW:/immutedata=RO -o cow /data This mounts the filesystem exactly how I want to. Now I need to incorporate it into the automounter so that it's remounted upon demand. What I tried in…
Árni St. Steinunnarson
  • 131
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1 answer

Overlayfs reload with multiple layers (migration away from aufs)

I've come across one of those aufs to overlayfs migration headaches. With aufs you could specify multiple RO-layers and updating some files in them was refreshed with remount. fstab with aufs: aufs /etc aufs …
Manwe
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How will union mounts be possible in 12.04?

I noticed today that Ubuntu 12.04 will not include aufs. What, if anything, will be available to facilitate the creation of union mounts?
ændrük
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votes
2 answers

How to unmount unionfs-fuse filesystem

I have mounted a directory with the following command sudo unionfs -o cow,max_files=32768 -o allow_other,use_ino,suid,dev,nonempty stuff-linux64=RW stuff How do I change stuff-linux64 from RW to RO and add another directory (stuff-update64) on…
sk8nfool
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votes
1 answer

Make Ubuntu 16.04 "live" (read-only with read/write layer)

I want to set up Ubuntu 16.04 like a live CD. This worked great in Ubuntu 12.04 but with 16.04 there are problems. Services are crashing, CRON doesn't work, X doesn't work, I can't even login to the shell. So I think 16.04 needs some modification.…
Michael
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vote
1 answer

SSD as /tmp partition

I have a Ubuntu 14.04 server which has one drive where rootfs is mounted. I just added an SSD disk which I have mounted at /ssd Now I want my /tmp & /var/tmp to use this fast drive to speed up my server. First I wish to tackle just /tmp (and I know…
Anil Garg
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vote
1 answer

AUFS shared over SMB and NFS

I am using ubuntu server 12.04 as a file server with 3 disks, two contain files and one contains parity of the others, using snapraid. I have been able to share one disk as both SMB and NFS, but now I want make both disks show as one and share…
VortexDK
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How should I use Unionfs or similar in a computer lab to "freeze" /home?

Lab computers need to be "frozen." We'll be switching our XP lab of about 30 computers over to something else this winter, and I'm making a couple of proposals, one of which is LTSP, and another is an immutable live-like system, updated monthly. My…
Bo Dang Ren
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vote
1 answer

I want to know how to format and mount a drive with UnionFS

I'm having trouble figuring out how to partition and mount my drive using UnionFs as my filesystem. I think I'm missing something basic but can't make sense of it. I see some posts stating they are installing Unionfs so I may be thinking about this…
DCcrypto
  • 11
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vote
1 answer

aufs Root File System On Usb Flash

I configured aufs as a Root File System On Usb Flash Drive by this article. So the first brunch is real root FS and it is read-only. The second brunch FS is in memory and it is read-write capable. Both brunches combined in one file-based…
BBK
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Compressing part of filesystem a second time

I have a laptop running Ubuntu 11.10. I've replaced the HDD with a 120GB SSD, and to save some precious disk space I utilized one of Steve Hanov's tips for optimizing Ubuntu to run on a USB key or SD card; specifically, I implemented his third tip,…
Tomas Aschan
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2 answers

Live USB changed files

I run Ubuntu live USB in Try Me mode. How to get all changed files and settings? Example: I boot live USB. I change light mode to dark mode. How to know what file is changed? I want to make own live USB with dark mode default.
tfstwbbnb
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How to use Mergerfs to have multiple disks for /home

My growing number of users and their growing projects is pushing towards the limit. Disk usage is touching 100% already for /home. I need to have a secondary HDD (/dev/sdb1), move some users to that device. Then finally, I'm trying to use mergerfs…
TarekEldeeb
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