Questions tagged [btrfs]
A volume-managing, snapshot-supporting copy-on-write (COW) filesystem included in the Linux kernel.
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Why is it recommended to add nodatacow to a VM image on BTRFS, but using a QCOW2 disk is ok?
As far as I know, it is recommended to disable copy on write for VM images to avoid performance degradation on BTRFS. However, no one recommends against using qcow2 disk image format, despite being a ...
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Error: extent not found. When booting from btrfs using grub2
I recently attempted to migrate from ext4 to btrfs,
made the @ and @home subvolumes, copied over everything to those subvolumes,
chroot into the installation and run mkinitcpio - P and grub install ...
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Is it possible to re-number ids of BTRFS snapshots created via Snapper?
It is not big problem, but it will be really better to manage, if I can re-number it and all holes are gone.
So numeration will be again 1,2,3 and instead of 17,99 and so on.
# | Type | Pre # | ...
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How do I mount a multi-volume BTRFS filesystem?
I had a btrfs filesystem that consisted of multiple devices. I created it by taking a single device (/dev/sda) and running mkfs.btrfs on it. I then added 3 more devices to that filesystem (/dev/sd{b,c,...
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Does BTRFS raid 10, support the failure of 2 devices?
According to this answer
The guarantee that BTRFS offers, which makes it looks like regular raid 10, is that each piece of data is guaranteed to exist on two distinct drives, so the filesystem will ...
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How can I solve my strange no space left on device on fedora?
I run a fedora 38 system on virtual box (7.0). Now I have a "no space left on device" problem.
# dnf list *docker*
Fedora 38 - x86_64 - Updates ...
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Examine disk usage of file tree, accounting for reflinks on Btrfs [duplicate]
Calculation of disk usage through du entails maintaining a set of all inodes represented by files under the tree, such that hard links will be counted only once with respect to total disk usage.
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BTRFS partition regularly becomes read-only
I have/home mounted on a btrfs partition and it regularly (after a few minutes) becomes mounted read only after which I need to reboot for it to become rw again. journalctl tell me the following:
$ ...
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Does snapper (creating btrfs snapshots) spin up or keep spun up my hdd?
I am concerned that:
snapper (when creating snapshots) might prevent my drive to go sleep or
when the drives are sleeping that snapper might wake them up?
If yes, how can I prevent that? My goal is ...
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Is btrfs balance recursive?
I run btrfs balance on a daily basis thanks to a systemd service+timer to try to keep my filesystem healthy over time (is it even a good idea?). The command I use is as follow:
btrfs balance start -...
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btrfs receive to <mount-point>/?
Suppose I have a BTRFS filesystem A with a read-only subvolume at <mount-point-A>/snaps/good-one. I want to create a BTRFS filesystem B (could be on the same or another machine) which will ...
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Why does btrfs /home/ partition keep mounting ro on login?
I'm having a problem with my /home mounted on /dev/sdb1 on a btrfs partition. It keeps mounting roeven after I booted from a USB stick, ran check and confirmed that it could be mounted rw. Why would ...
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What is the difference between BTRFS RAID1 and BTRFS RAID5 on 3+ devices?
According to "Examining btrfs, Linux’s perpetually half-finished filesystem", BTRFS RAID1 is said to be "guaranteed redundancy—copies of all blocks will be saved on two separate devices&...
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What's the best method to raid1 a btrfs and efi boot drive?
I have two NVME drives, one of which is already working as I want and I boot off of it: it has two partitions one for EFI, one for the BTRFS Linux filesystem.
Device Start End ...
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What is a btrfs "5 disk RAID 10" (or raid 10 with odd number disks)?
In this video the author says he went from four disk BTRFS raid 10 array to a five disk RAID 10 and it took about a week. But I'm confused, how does a five disk RAID 10 work? Raid 10 is two or more ...
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What optimizations are turned on with the mount option "ssd"?
"Debian 12 Bookworm Minimal Install w/BTRFS
" by JustAGuy Linux at 8:28 he sets an option for ssd,
mount -o ... ssd ...
What is the option ssd? When should it be used, and when should it ...
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Does Debian ship the documentation for btrfs?
While researching the answer for this question, I noticed there is a documentation page for man 5 btrfs that I see online. But I don't see that on Debian 12. Did this get shipped at all? How can I ...
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What is the mount option space_cache=v2?
"Debian 12 Bookworm Minimal Install w/BTRFS
" by JustAGuy Linux at 8:28 he sets an option for ssd,
mount -o ... space_cache=v2 ...
What is the option space_cache=v2? When should it be used, ...
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btrfs subvolumes: What is @rootfs and @?
In the video "Debian 12 Bookworm Minimal Install w/BTRFS
" by JustAGuy Linux at 8:28 you see the author run
mv @rootfs @
You see that @rootfs that is the subvolume that's been created but ...
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What is the point of `btrfs balance` on one device?
What is the point of doing btrfs balance on one device?
btrfs balance start /mnt
What benefit will that give if /mnt is hosted on a single drive?
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Upgrading from ext3/4 to BTFS vs fresh install?
According to Debian
Ext2/3/4 filesystems are upgradeable to Btrfs; however, upstream recommends backing up the data, creating a pristine btrfs filesystem with wipefs -a and mkfs.btrfs, and restoring ...
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Btrfs: To enable snapshotting of subvolumes, do you need to create seperate subvolumes dedicated for snapshots, for each data subvolume?
As an initial disclaimer, I'm in the camp of not wanting snapshots to include snapshots, Inception-style.
So for example if I have @ mounted at /, and @_snapshots mounted at /.snapshots, then since /....
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How to enable snapshots on a btrfs root file system on a transactional server?
I recently had to reinstall my OppenSuSE Leap 15.5 based home server after a severe crash. The installer suggested me the "transactional server" option. But once the system was again ready ...
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Is it possible to relocate the mount point of a btrfs subvolume within the same root?
I have created a btrfs subvolume in the path of /docker/nc/data. As shown below:
$ sudo btrfs subvolume list /
ID 256 gen 13908 top level 5 path docker
ID 257 gen 13877 top level 256 path docker/nc/...
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Overlay mount at btrfs
I multiboot several distributions
which are at separate subvolumes.
They are stored in a not standardised
layout.
I have some subvolumes which I want
mounted in a layered way.
I prefere to use aufs .
...
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Convert a BTRFS subvolume to a normal directory
So, let's say I have a BTRFS subvolume on the root subvolume that I wish to convert to a normal directory as quickly as possible, while also keeping hardlinks and reflinks intact. Is there an easy way ...
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Why does the btrfs-subvolume list command list all subvolumes?
Experimenting with BTRFS in a VM environment.
I have created 2 sub-volumes (flat structure)
ID 256 gen 13 top level 5 path @
ID 256 gen 9 top level 5 path @home
I have mounted the @ and @home under /...
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How can I back up Snapper snapshots using BTRFS send/recieve?
Experimenting on a VM with BTRFS & Snapper. I have been able to take snapshots, undochanges, delete snapshots, etc using Snapper.
It is not clear to me, how to back up the resulting snapshots to ...
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How can I get snapper to recognize a snapshot?
Background
I am playing around with BTRFS in a VM.
I followed this guide to make sure my /home/.snapshot folder is its own sub-volume. Everything seems to work, I can take snapshots, list snapshots, ...
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Where does grub-install take the arguments for grub-mkimage from?
When I run grub-install /dev/vda -v I see this line in the output:
grub-mkimage --directory '/usr/lib/grub/i386-pc' --prefix '(,msdos1)/boot/grub' --output '/boot/grub/i386-pc/core.img' --dtb '' --...
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Extend BTRFS LUKS partition
A few years ago I used this excellent guide https://www.youtube.com/watch?v=co5V2YmFVEE to encrypt my Thinkpad disk with LUKS and use BTRFS as my file system.
My SSD at that time only had 256GB, now I ...
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`cryptsetup open` fails with correct passphrase - "No key available with this passphrase."
I recently ran (essentially) rm -rf / --no-preserve-root on my LUKS encrypted BTRFS root filesystem. I'm trying to mount the drive from an endeavouros (arch) liveusb, without success.
I created a ...
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btrfs used size doubled after replace operation
I had to replace a btrfs RAID1 device today. This is the filesystem status before the operation:
$ btrfs filesystem show /mnt
Label: none uuid: b19e1a48-a25b-4f63-941d-c009949a5d51
Total ...
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Speeding up rsnapshot backups to btrfs?
I'm using rsnapshot to back up the computers on my home network. For years, I've been using Ext4-on-LUKS on USB hard disks and getting good results. Recently I added a Btrfs-on-LUKS disk to get the ...
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BTRF bad block force realloc
I have a failing hard drive, which only have 3 bad blocks. I wanted to force these blocks to reallocate but i'm unable to find the block what i have to rewrite.
Here is the error message:
BTRFS ...
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How to create a data-redundant encrypted filesystem on an external SSD?
What's the easiest way to format an external SSD with encryption and RAID1-style data replication?
As I recently grew suspicious of my SSD+luks+btrfs setup, I've started wondering how to reduce risk ...
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Which is the better way to get scattered partitions on Arch Linux to install for legacy (BIOS) + Btrfs + Luks encryption?
There is in my hands, an old i3 laptop that I wanted for study and lab schooling use. Since it is a laptop, I would like to increase the security and further install flexibility.
I'd like to have the ...
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Any more ways I could try to get my out-of-space Btrfs data-raid6 mdata-raid1c4 volume operational again?
The volume consists of 9 disks total, one of them has plenty of space (the new one I had added shortly before running out of space), one with only 289 MiB of free metadata space, and all the others ...
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How to measure the role of btrfs in SSD wear on my PC?
I've used btrfs for my encrypted partitions (luks) on Samsung EVO SSDs. The disks failed faster than expected. How can I assess whether e.g. ext4 would be more reliable on these disks for my usage, or ...
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BTRFS folder suddenly shows up as a file
So, I have a BTRFS drive and a folder that contains videos from my capture card moved to a folder on the drive. I was trying to check what videos were in the folder and went to cd into it, but instead ...
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In btrfs-check, how to automatically or manually fix the error "errors 2000, link count wrong"
I run btrfs-check and got the following errors:
$ sudo btrfs check --progress --force /dev/nvme0n1p7
Opening filesystem to check...
WARNING: filesystem mounted, continuing because of --force
Checking ...
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how to access linux data from another machine physically?
My laptop is failing, but I know for sure the hard drive is okay and fine.
I want to take the data inside it, I connect my laptop's hard drive (open suse tumbleweed with btrfs filesystem) to my ...
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Cannot mount btrfs subvolume
I've got a big old BTRFS RAID array with a few subvolumes:
# btrfs subvolume list -u /bulk
ID 256 gen 56429 top level 5 uuid 11b16b2e-8f75-ec46-8cgd-4a001c70a4ba path @
ID 257 gen 56428 top level 256 ...
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i have a very messy situation with grub lost and a potentially corrupt partiton
SO, we start off with, this reddit post after that i understood that the issue was arising because i was using btrfs and root00 and home were subvolumes.
However, before i understood this, i tried to ...
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btrfs configurations for various subvols
Is there a recommended for how much to compress various subvolumes based on their use purpose?
In my case, I have subvols @, @home, .snapshots/@root, .snapshots/@home, @srv, var/@log, var/@cache. This ...
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BTRFS snapshot fails with "No space left"
While creating a BTRFS RAID10 subvolume snapshot, I hit:
[21816375.986061] ? btrfs_cleanup_transaction+0x530/0x530 [btrfs]
[21816375.986065] kthread+0x112/0x130
[21816375.986066] ? kthread_bind+0x30/...
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How do fstrim and BTRFS SSD optimizations work for both SSD's in a RAID1?
First apologies if this has been asked before, but I could not find any link with any combination of keywords.
My question is - How do SSD optimisations work in BTRFS in a RAID1 where both devices are ...
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Can I use btrfs subvolumes for trying multiple Linux distributions without commiting a set quantity of disk space?
With filesystems like ext4 if I want to try a new Linux distribution I have to first shrink existing partitions then create a new partition that's locked to a certain size where I can install the ...
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rsync implications of ACL backups between different source & dest file systems
I'm having an issue using rsyncd (the daemon-ized version of rsync) to back up files from my macOS to my Synology server. Here's the command that fails:
% rsync -rlcAXtgoDiv --fake-super ~/scripts ...
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For Btrfs, how to convert to DUP =3 or >3 on a single partition?
The question refers to:
Debian based Linux, kernel >=5.1
explicitly also to systems with only one single harddisk or SSD, with only one Btrfs partition
Hints on a possible implementation:
"...
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