btrfs is a B-tree based, copy-on-write filesystem for Linux. It's main features include snapshots, checksumming of data and filesystem level RAID support. It's similar to [tag:ZFS].

learn more… | top users | synonyms

0
votes
1answer
34 views

BTRFS: “no space left on device”, but btrfs command says otherwise

I am using BTRFS to create a RAID0 volume from 2 disks. Both are on an AWS EC2 instance with 30 GB space available each. The command I used to create the filesystem is: btrfs -d raid0 -L MYLABEL /dev/...
0
votes
0answers
25 views

btrfs, Force bad checksum recalculation

A large, USB-connected HDD with btrfs contains a 1TB file (a disk image). The first btrfs scrub after writing that file found 3 logical bad blocks developed somewhere in the middle of that file: [ ...
4
votes
1answer
29 views

Linux no modify time (nomtime)

Is there a way to disable the mtime of an filesystem? There is an Filesystem independend noatime Option, but no "nomtime". Also in the Filesystem specific documentation for ext4 and/or btrfs i couldn'...
1
vote
1answer
30 views

Seeking inside file performance under BTRFS with LZO compression

I am planning to use btrfs on a 50 TB RAID6 array and I want to enable lzo compression. This is for bioinformatics setup where lots of seeking within large (1 TB -- 20 TB) files occur. (The software ...
2
votes
1answer
47 views

btrfs increase raid capacity by replacing disks (and not adding disks!)

I'm very excited about the new features of btrfs and would like to start tesing it. Before I get started, I would like to ask if btrfs supports increasing raid capacity by replacing disks by bigger ...
0
votes
0answers
59 views

btrfs will not delete device although there is enough unallocated space

I have a btrfs filesystem set up with 2 partitions - each 2,7 TB. Btrfs version is 4.4 btrfs version --> btrfs-progs v4.4 on Ubuntu 16.04 This is the current status and the result of a previous ...
0
votes
1answer
20 views

Add menu entry in grub2 for os on btrfs partition

How can I add a menu entry in grub 2 for an os on a btrfs partition? Currently update-grub does not detect an os on a btrfs partition.
0
votes
0answers
15 views

Fixing smartd errors on btrfs raid 10

I had some errors during smartd test May 5 10:08:05 c3po smartd[856]: Device: /dev/sdb [SAT], 236 Currently unreadable (pending) sectors May 5 10:08:05 c3po smartd[856]: Device: /dev/sdb [...
4
votes
0answers
59 views

Can Btrfs use SSD for metadata and leave bulk data on HDD?

is it possible for Btrfs to use SSD for metadata only & leave bulk data on less costly storage such as HDD? I refered to this page Using_Btrfs_with_Multiple_Devices and can not find a solution. ...
0
votes
0answers
59 views

Merge btrfs subvolumes of lxc container

Problem: I've made some snapshots of an lxc container in the past. When I tried to make one earlier using the command lxc-snapshot -n base -c commentfile it echo'd Container is not defined. I ran that ...
2
votes
1answer
104 views

Is this btrfs snapshot removal performance normal?

I have several boxes running Debian 8, dovecot and btrfs. I'm using btrfs snapshots for short term backup. For this purpose I keep 14 snapshots of the mail subvolume. Performance is OK until it comes ...
0
votes
1answer
17 views

BTRFS remove directory from snapshot

There is the: btrfs subvolume delete <subvolume> command for deleting snapshots, but is there any solution if you need to delete a single directory from 60 snapshots? Not possible with rm -...
0
votes
1answer
315 views

Why is zfs/btrfs recommended for an lxd host?

Note that for maximum performance, it's recommended to have /var/lib/lxd on a btrfs filesystem or setup ZFS or LVM and configure LXD to use a ZFS pool or LVM VG. Source Why is that? I.e. How ...
0
votes
0answers
107 views

Btrfs multiple devices with dm-cache

Unlike md-raid, when you create a btrfs file system with multiple devices, there is no special block device exposed (ex. /dev/md0). With the lack of built in cache support (ex. L2ARC), can one set up ...
1
vote
2answers
31 views

Copying between lzo compressed BtrFS's: de/re-compressing?

I'm copying a large number of files between two lzo compressed BtrFS filesystems on different drives mounted on the same machine. It appears that the files are being de/re-compressed. Is there a way ...
2
votes
2answers
163 views

How to find the file at a certain btrfs inode

I have a corrupt file according to btrfs BTRFS info (device sdb1): csum failed ino 367 off 310013952 csum 1601485211 expected csum 3692975992 I assumed ino 367 means inode 367, so I can use find ...
1
vote
0answers
133 views

Can't mount BTRFS with write permissions. Btrfs check crashes (Core dumped)

I was using btrfs filesystem for some time on one of my external drives mainly to test deduplication and everything was working just fine. Unfortunately yesterday when I mounted the partition I ...
2
votes
0answers
119 views

btrfs write operations hang when appending to files

When writing sequentially to files on my large-ish (70 TiB) btrfs filesystem, I am noticing that something is causing prolonged write blocks (seconds to several minutes). This is inconvenient at best ...
1
vote
2answers
62 views

Do I need btrfs scrub if a lower layer also scrubs?

I have a multi-TB btrfs made up of virtual disk images that live on NetApp NFS filers. The data are redundant at the NetApp level, so the btrfs is RAID-0. In addition to providing redundancy, the ...
0
votes
0answers
143 views

I'm unable to mount a btrfs partition

I had a raid 5 array of 3 disks using btrfs (raid provided by btrfs) one of the disks was damaged and I replaced the disk via: btrfs device add /dev/sdc /media/raid/ btrfs device delete missing /...
1
vote
1answer
214 views

How to btrfs check a root partition

I'm sure the reason I'm having a brain fart is because it's late, but how can I go about performing a btrfs check on the root partition? The device needs to be unmounted, which can't happen because ...
0
votes
0answers
100 views

Cannot remove stale file on btrfs

I have a btrfs filesystem which in one directory has the following entry: -????????? ? ? ? ? ? 1448367601.M899489P12992.mst19,S=8958,W=9072:2,S I cannot remove this file, every operation ...
0
votes
0answers
29 views

btrfs - how list/find snapshots by age

I've been using a simple shell script to manage my snapshots and I'm happy with it -- so please don't suggest that I start using snapper or something else -- but I'm now looking to increase the ...
1
vote
0answers
182 views

LXC Snapshotting on Ubuntu 15 and BTRFS file backend

i have a dedicated server with Ubuntu 15 Wily and i want to play/study with LXC. My main goal is to snapshot and clone containers without stopping them, and for so i have formatted a partition with ...
1
vote
0answers
113 views

Why is ReFS not appropriate for Work Folders

I'm looking to setup a NAS for a small team. Two main requirements are using it as an archive and a folder syncing. Because I want to make sure that the archive is not prone to bit rot, I've came to ...
-1
votes
1answer
377 views

Ubuntu + ZFS vs Rockstor [closed]

I have a personal fileserver at home with 6 HDs: 1 500 GB one for the OS 1 4 TB one for temporary data four 2 TB ones that we want to configure in some sort of RAID 5 fashion It looks like I have ...
2
votes
2answers
361 views

rsnapshot vs zfs / btrfs snapshots

Currently I'm using rsnapshot to implement a daily / weekly / monthly backup scheme on an external disk. Lately I've been reading alot about copy-on-write file systems like zfs and btrfs. I quite like ...
0
votes
1answer
150 views

Multiple btrfs volumes with different RAID levels on the same devices

I have two disks - one xGB and one (2x)GB. I would like to have one mountpoint from these disks under raid0 and one under raid1, spread over the total available space. Is that possible with btrfs ...
1
vote
1answer
219 views

More available space than expected using btrfs RAID10?

I had just created a btrfs RAID10 array in my Ubuntu 14.04 box for the first time by using the command: mkfs.btrfs -d raid10 -m raid10 /dev/sda /dev/sdb /dev/sdc /dev/sdd My 4 hard drives are each ...
2
votes
2answers
225 views

ext. 2-bay USB-Drive with RAID: btrfs RAID vs built-in RAID

For backups I want to use an external USB3 Drive: two HDD with RAID 1 (mirror) in one 2-bay enclosure. As filesystem I'll use btrfs because of subvolumes and checksums. Performance isn't important, ...
1
vote
1answer
132 views

How much usable space will a 2TB+2TB+3TB+3TB btrfs filesystem have with data in RAID-1 mode?

I have a pair of 3TB drives in a btrfs filesystem, and I wish to expand this filesystem by adding two more 2TB drives, using the btrfs device add command. Data in the current filesystem is mirrored in ...
2
votes
1answer
46 views

BTRFS new device cannot be added

I have a raid10 setup with btrfs with 5 disk currently: Total devices 5 FS bytes used 6.89TiB devid 1 size 3.64TiB used 2.83TiB path /dev/sde devid 2 size 3.64TiB used 2.83TiB path /dev/sdd ...
-1
votes
1answer
182 views

Balanced btrfs filesystem using different amounts of space on each disk

I recently upgraded a desktop server with 2 drives (1TB+3TB) drive to one with 1x1TB and 3x3TB drives. In the process, I installed btrfs and raided the 3TB drives together, leaving the 1TB drive as a ...
1
vote
0answers
113 views

btrfs send from a 3tb drive ti btrfs-receive on a 1tb drive

I have question about the nature of a subvolume Snapshot sent and received. I have 2 3tb raid1 drives with only about 300gbs on them. I have a spare 1tb drive I placed in an enclosure for backups. ...
3
votes
1answer
72 views

Does btrfs share file parts across snapshots?

I know that modern filesystem snapshots take very little space until they start to diverge by changes in files. However, I have been unable to identify at which granularity btrfs manages the changes. ...
0
votes
1answer
410 views

How do I use 2 disks for CoreOS?

I've got a bare metal server with 2x 480gb SSD disks. I will run a CI server with docker on CoreOS. Do I have to add another small disk to hold CoreOS and mount the 2x SSDs as /var/lib/docker?
3
votes
2answers
411 views

Removing files takes too long

Short version: rm -rf mydir, with mydir (recursively) containing 2.5 million files, takes about 12 hours on a mostly idle machine. More information: Most of the files being deleted are hard links to ...
2
votes
1answer
686 views

BTRFS, sector alignment and Advance Format Disks

I want to set up a BTRFS RAID1 setup with two WD Red 4TB disks, which possess 4K sectors. Since I am keen to get it right the first time before copying data to it (yes it will be backed up), my ...
3
votes
1answer
446 views

Directories inside /var are on root partition not /var partition

Few weeks ago I installed Opensuse 13.2. I partitioned the disk so that root '/', /var, /tmp and /home are on different partitions. Today I noticed that although /var is on partition sda8, all ...
2
votes
1answer
87 views

Using grml with btrfs

I'm trying to boot an ISO using grml and grub on a BTRFS root. However, after selecting the boot option from the menu grub (or some subsequent loader) fails to find the iso /@/boot/grml/ubuntu-14.10-...
1
vote
0answers
131 views

Snapshot of BTRFS Device on top of luks Volume

I have the following problem: I can't figure out, how to create a snapshot of a btrfs volume residing on a crypted disk. This is the setup: /dev/sdb is a 1TB USB 3 disk. it has a partition /dev/...
1
vote
1answer
530 views

Can't delete a btrfs snapshot

I have a system that creates periodic btrfs snapshots and deletes old ones. Today, I've started receiving warnings that the system can't delete some old snapshots. This is the output I get: root@...
1
vote
1answer
114 views

BTRFS raid with odd number of devices

I used to have RAID10 btrfs setup with 4 disks. Now I added sdf a new disk (its doing the balancing): Total devices 5 FS bytes used 5.73TiB devid 1 size 3.64TiB used 2.78TiB path /dev/sdd devid ...
2
votes
1answer
425 views

Can I mount a read-only btrfs volume across multiple machines?

Is it possible to have a single btrfs mounted volume read-only mounted across multiple machines? Can one of the hosts mount it read/write to provide updates to the others? The reason I'm asking this ...
1
vote
1answer
481 views

Mounting compressed filesystem using FUSE

I'd like to move some folders on my computer to a compressed read/write images, so I could get it to take less disk space on my machine (the folders contain some Mercurial and Git repositories). ...
5
votes
2answers
2k views

btrfs Integrity and Stress Testing

A DevOps colleague is recommending that we begin transitioning our production environment to using btrfs. We have primarily ext4 filesystems, though some low-usage servers using ZFS (on Linux). As ...
1
vote
1answer
743 views

recovering a corrupt degraded btrfs RAID6, need to manually clear an inode

I have a btrfs RAID 6. I have lousy hard drives, one failed, and another failed during recovery. Now I am without parity and cannot rebuild--a third drive is throwing read errors on a few sectors. ...
-1
votes
1answer
230 views

btrfs formatted partion not mounting from fstab

I have this new mageia 4 setup with some btrfs partitions. My root "/" is on btrfs, working fine. from fstab: UUID=b2b0263e-a04a-4bd7-86d7-d2ec19a90b84 / btrfs relatime 0 0 then I have a different ...
6
votes
2answers
7k views

How to delete a btrfs snapshot?

I'm new to btrfs and I am trying to delete some snapshots I made a few months ago. They're taking up about 20GB of space, and I need that space back. This seems to list the snapshots: ↪ sudo btrfs ...
11
votes
3answers
4k views

Proper way of handling LXC containers on btrfs

Lets say we have one server with lxc installed, and a lxc container used for as a base img /var/lib/lxc/ubuntu_base. For simplicity let's forget the config changes after copying the base img. some ...