Questions tagged [union-mount]
A union mount creates an overlay of several filesystems on one mount point
24 questions
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Union mount for Linux where lower directory's contents are protected
Suppose on a Linux system that, like macOS 10.15+, we have two directories /System/Volumes/Data/Applications ($SVDA) and /System/Applications ($SA). $SA is supposed to be protected. We want to create ...
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How to instruct systemd to use a specific unionfs for /home
Context:
Say I have two workplaces. Currently, I carry a laptop along, and have external HDs staying in these workplaces to hold backups. Now, I'm given the opportunity to have a desktop in both ...
- 1,523
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Overlayfs as a solution to copying central file systems everywhere. In what way?
I have searched the whole internet and have watched my lecture multiple times just to understand one thing: I still can't quite understand, how is overlayFS a solution to copying the central FS for ...
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How to appropriately set spindown (Power Management) when using SnapRaid?
I run openmediavault 4.1 and changed from RAID6 to SnapRaid with 7 hard drives for data plus parity.
I remember reading installation advice on RAID setup that said "never set spindown for HDD&...
- 549
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Using unionfs or similar as root file system in Linux?
After building Linux From Scratch several times I realized that package management is really a hard thing to do. After thinking for some time, I came across an idea. My idea is to install all packages ...
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Does remounting after changes to overlayfs underlying filesystem (UB) necessarily restore consistency?
The overlayfs documentation states that "if the underlying filesystem is changed, the behavior of the overlay is undefined, though it will not result in a crash or deadlock."
And, indeed, I'...
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How to create a union mount (bind two or more directories to one mountpoint) on illumos / solaris?
I have been using union mounts, such as unionfs on FreeBSD or mergerfs on Linux, and now I would need to do the same on illumos (SmartOS).
Reading illumos or SmartOS man pages is not helpful. Same ...
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Overlay : filesystem not supported on lowerdir
I tried to mount an external storage device (a usb flash drive) with overlay (as the lowerdir the usb and as upper a temporary ramdisk)
mkdir /data
mkdir /data/lower
mkdir /data/rw
mkdir /data/root
...
- 113
1
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1
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FUSE overlay mount with colon in path
Is it possible to do an overlay mount when one of the paths has a colon in it? All of the FUSE overlay mounting solutions I've looked at use a colon to separate the paths in the overlay, and I can't ...
- 151
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How safe is it to use unionfs in FreeBSD?
From man mount_unionfs:
BUGS:
THIS FILE SYSTEM TYPE IS NOT YET FULLY SUPPORTED (READ: IT DOESN'T WORK)
AND USING IT MAY, IN FACT, DESTROY DATA ON YOUR SYSTEM. USE AT YOUR OWN
RISK. BEWARE OF DOG. ...
- 1,311
2
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2
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419
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How to use loopback to access the lower files of a unionfs, in FreeBSD?
From man mount_unionfs:
If a file exists in the upper layer then there is no way to access a file
with the same name in the lower layer. If necessary, a combination of
loopback and union mounts can ...
- 1,311
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4
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Mount /var/logs as tmpfs, with help of overlayfs to save changes sometimes
Instead of just mounting tmpfs on /var/log I want to use overlayfs.
/var/log are writable tmpfs, but containing files were there before
tmpfs mount. This old files are not in memory of tmpfs but in ...
- 270
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5
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Merge changes to upper filesystem to lower filesystem in Linux Overlay (OverlayFS) mount
I would like to be able to merge changes from the upper filesystem of an overlay mount to a lower filesystem.
I am interested both online (i.e. merge while the overlay is mounted) and offline (...
- 661
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1
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Union mount options in Fedora
I've grown up a Debian/Ubuntu guy and I'm learning Fedora by trying to recreate the services my Ubuntu trusty box currently provides. However, I'm trying to recreate a union mount and don't see any ...
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Why mounting overlayfs with root as lowerdir produce an empty /proc in mergedir?
Here's the test case:
#!/bin/bash
more="$@"
saved="$EUID"
if [ "$EUID" = "0" ]; then
echo "don't run as root"
exit
fi
m="/tmp/mount-point"
exec sudo unshare -m /bin/bash <<UNSHARED
...
- 343