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13
votes
1answer
1k views

Limit on the number of btrfs snapshots?

I am considering using btrfs on my data drive so that I can use snapper, or something like snapper, to take time based snapshots. I believe this will let me browse old versions of my data. This would ...
11
votes
1answer
7k views

ZFS Snapshot to file as Backup with rotation

I have a local FreeNAS system and want to use ZFS snapshots for backups. FreeNAS has the built-in Replication Tasks which use zfs send snapshot_name to send a snapshot to a remote system. But this ...
9
votes
1answer
158 views

Rolling back btrfs subvolume with child subvolumes

Is there a canonical way of rolling back to a subvolume snapshot that has child subvolumes. So for example, this is my btrfs volume layout: ID 257 gen 59802 top level 5 path __active ID 258 gen 59784 ...
8
votes
4answers
7k views

`cp -al` snapshot whose hard links get directed to a new file when edited

I am trying to take snapshots of a massive folder regularly. I have read here: http://www.mikerubel.org/computers/rsync_snapshots/#Incremental that cp -al takes a snapshot of a folder by simply ...
8
votes
1answer
2k views

GNU/Linux: overlay block device / stackable block device

GNU/Linux has union mount that overlays dirs. So you can mount a writeable dir on top of a read-only dir. When the writeable dir is unmounted the read-only dir is untouched. I am looking for the same ...
8
votes
1answer
496 views

Do LVM snapshots ultimately cause fragmentation?

I'm planning on using LVM in order to be able to take atomic snapshots of large files and rsync them to a remote site. What I'd like to know is whether there is any long-term impact on the main (non-...
5
votes
3answers
2k views

Performing accurate snapshot and incremental backups to a remote server

I have a few Ubuntu (and potentially RHEL) servers I'd like to back up to a central backup server (via rsh/SSH). I'd like to do both snapshot and incremental backups. The goal is that if one of the ...
5
votes
2answers
4k views

How to delete btrfs subvolumes with <FS_TREE> in their name

I have a bunch of btrfs snapshots like so: 20:17:37 [root@galaxy /]$ btrfs subvolume list -a / |grep apt ID 271 gen 348 top level 5 path <FS_TREE>/@apt-snapshot-2013-04-17_21:44:30 ID 272 gen ...
4
votes
1answer
616 views

Online remount btrfs of root filesystem with different subvolume (snapshot)

Let's say you have a btrfs root filesystem on an online system. You want to revert the filesystem to an earlier state, of which you have a snapshot: remount /dev/sdaX / -o remount,subvol=snapshots/Y ...
4
votes
0answers
267 views

Restore Btrfs snapshot from subdirectory to parent

I have a Btrfs partition which has a single subvolume at the top level (/root). It has subvol=root option in /etc/fstab. Every week, I take a readonly snapshot into /root/snapshots/... using: btrfs ...
4
votes
0answers
637 views

Compiling and running Snapper for Ubuntu

I am trying to get snapper working in my Mint 14. (The version from launchpad is old and not compatible with Ubuntu 12.10. The OpenSuSe's build project failed to build it, too). So I try my luck with ...
3
votes
1answer
126 views

Is it possible and how to merge identical files between different snapshots in a btrfs file system?

I regularly use btrfs's snapshot to backup the whole system, but it's redundant to have identical files between different snapshots. Commonly, for example, I took a snapshot of @ as @...
3
votes
3answers
2k views

Temporary restore LVM snapshot of root

I have a snapshot of the root filesystem that I want to boot with - bring the machine into a state it was a few days ago, run some tests and then go back to where I am right now. I tried editing ...
3
votes
1answer
496 views

What privileges are needed to delete a read-only btrfs subvolume?

I want to delegate non-root user to delete read-only subvolumes (snapshots). What exactly capabilities/rights I need to grant, so that he can remove his own read-only snapshots? I've already ...
3
votes
1answer
2k views

How much can the space allocated for an LVM snapshot be reduced?

I created an LVM snapshot, then I modified the original logical volume, and now I see that I probably allocated too much space to hold the snapshot. And I want to reclaim some free space by reducing ...
3
votes
3answers
2k views

Difference between fsfreeze and lvm snapshot

I heard recently about fsfreeze and I'm very interested in making snapshots of my VM with VMware and get a consistent state of disk using quiescence. All my file-systems are LVM volumes, and man ...
3
votes
1answer
363 views

Snapshot large changing files

At home I have the following backup scheme: All machines daily rsync to the servers $FULL_COPY directory. The server takes snapshots of that directory daily (also weekly/monthly), keeping at most X ...
3
votes
0answers
268 views

LXC with both GUI apps and snapshots on unmodified Fedora kernel

I am looking for a tool or library to run LXC that supports: running X applications conveniently snapshotting root filesystems (using a Fedora system with an unmodified kernel), so that I don't have ...
3
votes
1answer
348 views

Having trouble with LVM snapshot

I have a funtoo linux machine which I am trying to add ubuntu to (thats a whole other issue). It is encrypted with luks and has lvm on top of that. I have a 2 TB harddrive (sdb) which I would like ...
3
votes
1answer
344 views

Create Logical Volume Snapshot at boot and before mount

I'm using Kubuntu 11.10 and before I upgrade to 12.04, I want to make snapshots of my filesystems. Coming to think of that, I realized that it can be very useful to create snapshots of logical volumes ...
2
votes
4answers
3k views

How are filesystem snapshots different from simply making a copy of the files?

by doing this, # btrfs subvolume snapshot /mnt/1 /mnt/1/snapshot # tree /mnt/1 /mnt/1 ├── a ├── snapshot │ ├── a │ └── subv └── subv └── b 3 directories, 3 files We can create snapshot ...
2
votes
1answer
156 views

Can you do a btrfs snapshot of a live system?

I am planning on giving btrfs a try soon, and what I want to know, and can't seem to find online is this: Can you do a btrfs snapshot on a running system if the snapshot is not just of some small ...
2
votes
5answers
196 views

space-efficient disk snapshots on Linux

I like the ability of VirtualBox to instantly create and restore snapshots and I was wondering, if it's possible to do similar things on the host machine. First I looked at lvm snapshots, but some ...
2
votes
1answer
61 views

Transfer content of LVM block device ensuring consistency - LVM snapshot?

I need to create off-site full backups of an LVM block device. Thinking the old dd over SSH method. To ensure I have a consistent backup, should I create an LVM snapshot first? So new changed blocks ...
2
votes
1answer
208 views

Configure Snapper/snapshots on Fedora 23

I am getting an error while trying to configure snapper on F23. My root partition is btrfs, and I have installed the snapper package. The error is occurring when I initially try to create the default ...
2
votes
1answer
4k views

How to take snapshot of an ext4 filesystem

Is there any way we can take a snapshot of an ext4 filesystem so that we can revert back to it later?
2
votes
2answers
141 views

How can I capture a consistent snapshot of a directory and all its children?

We have an application that periodically backs itself up to a directory on the local file system. Inside this directory are several more files and directories. I want to produce a "snapshot" of all ...
2
votes
1answer
194 views

Snapper to only take snapshots if something has changed, or at a lower cadence

I'm using snapper for automatic timeline snapshots of my filesystem. The issue I have is that it continues to take hourly snapshots even when nothing on the filesystem has changed, which causes the ...
2
votes
0answers
198 views

How do I align my new btrfs default subvolume with the real root of my filesystem?

I rolled back my system by using snapper rollback Unfortunately this caused my current default volume to not be at the root of my filesystem anymore. As you can see in this screenshot: The ...
1
vote
4answers
520 views

Creating a snapshot of a linux system

I want to do the following - Save the current state of my linux OS(centOS6.5). Do some changes (more specifically inject a fault and test some service to check how it behaves when that particular type ...
1
vote
1answer
2k views

Qcow2 snapshots - snapshot for disk vda unsupported for storage type raw

I am running a KVM server (Ubuntu 14.04) and would like to take snapshots of my guests. I was reading how about how to do that in this article. It seemed as if I should be able to take a snapshot of a ...
1
vote
1answer
105 views

btrfs snapshots without subvolumes?

I'm starting to use btrfs. I want to be able to snapshot certain directories but do not want to create sub-volumes. Is this possible?
1
vote
2answers
76 views

Snapshot of drive

Does technology exist which allows you to take an instantanious snapshot of a drive? At the moment, I am using dd which takes a few minutes to create an image of a usb drive to my hdd. Is it ...
1
vote
1answer
19 views

LVM snapshot - performance for write-only data

I have a client that is archiving write-only , time-series data in a database (ie. data is rarely modified after it is written, and it is rarely read as it is on a secondary/backup/failover node). I ...
1
vote
1answer
56 views

Install a specific old package with dependencies

I need to install a specific version of tomcat (6.0.16) using apt-get install with dependencies from an old Debian repository. Old repositories can be found at: http://snapshot.debian.org/archive/...
1
vote
1answer
203 views

LVM Snapshot mount read-only or not?

In this page of Linux LVM Howto it's said that "LVM2 creates read/write snapshots by default". In this other page of Red Hat docs it's said that "Because the snapshot is read/write, you can test ...
1
vote
2answers
1k views

Should I be worried? Segfaults reported in syslog when merging LVM snapshot (reverting the original back to the snapshot)

I was just experimenting with snapshots in LVM on Ubuntu 12.10. I created a snapshot logical volume of 6.5 GiB, and after making some changes to the origin decided to merge the snapshot back in to ...
1
vote
1answer
35 views

How to isolate snapshot volumes with btrfs?

If I create a snapshot of root with: btrfs subvolume snapshot -r / /snapshot-$(date +%s) I can then see this snapshot with ls / How do I make snapshots that are isolated from the volume that they ...
1
vote
1answer
39 views

Snapshot size in lvm

I am trying to understand how to select a proper size for snapshot. As I know simple snapshot uses space which is needed for covering difference between two logical volumes. So, what size of snapshot ...
1
vote
1answer
141 views

btrfs - snapshot of a parent subvolume excludes child subvolumes?

Let's say I want to exclude ever-changing logfiles from backups. Parent subvolume / Child subvolume /log I snapshot /. Looking at the snapshot, /.snapshots/today/log will be empty, correct? This is ...
1
vote
1answer
40 views

Back up snapshots without being admin

I would like to make a back up/snapshot of a folder where I have built various programs (~4.1 GB in size). The idea is to be able to quickly restore everything in this path to it's original state in ...
1
vote
0answers
18 views

IO Error when trying to create a Btrfs snapshot

In Fedora 23, my / partition is formatted as Btrfs: /dev/nvme0n1p4 / btrfs rw,seclabel,relatime,ssd,space_cache,subvolid=257,subvol=/root 0 0 Full output: $ sudo cat /proc/mounts sysfs /sys sysfs ...
1
vote
0answers
18 views

Snapper - how to undo changes, preserving timestamps?

I've damaged modification dates of files on my drive and I wanted to revert them using snapper snapshots but it doesn't seem to work, snapper only reverts content of files not modification dates. ...
1
vote
0answers
29 views

using motion to trigger snapshot when movement stops

I am trying to use motion software (but I could use just any other linux software) in order to "log" some manual work by snapshots. So imagine I wanna make a stop-motion film with my LEGO(r) toys (...
1
vote
1answer
118 views

Using Device mapper thin provisioning on loop devices

I have several KVM raw files that are read only (about 100gb). I am adding these raw files as loopback devices. I then create a snap file to allow the VM to have read/write access to its disk. This ...
1
vote
0answers
48 views

How many btrfs snapshots is too many? [duplicate]

I've been doing daily snapshots on a btrfs subvolume for nearly 3 years, resulting in over a thousand snapshots. I am experiencing occasional small stalls (a few seconds) in basic filesystem ...
1
vote
1answer
86 views

When using dm-cache, how do you do snapshots on a cached LV?

In dm-cache, how do you do snapshots on a cached LV? I attempted the usual way on a CentOS 6.7 installation and got the following results:- # lvs LV VG Attr LSize Pool ...
1
vote
0answers
594 views

Creating ISO Bootable Image from a CentOS (Linux) system

I have a Linux machine (CentOS 5.8) on which I have installed multiple applications and tools (with yum and few others after compiling the source code) on it. As I have spent considerable time in ...
1
vote
0answers
398 views

Centos web camera, fast application for snapshot?

I'm using ffmpeg for taking snapshots / still images with web cameras. I'm going to use several web cameras to take photos at the same time or one after the other (timelapse). It's important for me ...
1
vote
0answers
78 views

how can I backup and restore of partitions and logical volumes?

This is my disk scheme sda1 /boot ext4 sda2 /somefiles ext4 sda3: lvm volgroup1/lvolume1 / ...