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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 ...
0
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0answers
18 views

KVM snapshot slow booting after some time

I'm using Red Hat system and using KVM for virtual machines. Currently I have 8 snapshots in my virtual machine called "Win7", where each snapshot is built based on the snapshot before to fix some ...
0
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0answers
20 views

The snapshot is masked, not in raw colors

I capture screen using gnome-screenshot 3.18.0. When we select the region to capture, the region is masked and becomes blue. When saving to picture files, the snapshot is expected to be back to raw ...
0
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1answer
53 views

taking snapshots of a BTRFS volume mounted with nodatacow?

I plan to create two subvolumes on a BTRFS-formatted spinning disk. I plan to mount one of those subvolumes with nodatacow so that I can efficiently store virtual machine images and database files ...
1
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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
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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 ...
0
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1answer
19 views

LVM Snapshot - Copy on write - does it apply to new data?

I have been reading about LVM Snapshots, and I have a general understanding of how it works. If a snapshot is made of source data, I understand that the copy-on-write (COW) means that if a ...
1
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1answer
55 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
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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 ...
0
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1answer
22 views

Restore a disk from a snapshot in XEN 4.6

I created a snapshot with lvcreate -n snap01.vm01 -L 5G -s vg0/vm01.eclabs.de now I did some stuff on my disk i don't want to keep and want to revert it to the snapshot point. How do I restore ...
1
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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
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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
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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 ...
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
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 ...
0
votes
1answer
62 views

Solaris 11 /var used significant space, but I cannot see it on filesystem

I have a mirrored rpool: NAME USED AVAIL REFER MOUNTPOINT rpool 72.1G 1.22G 39.5K /rpool rpool/ROOT 67.9G 1.22G 31K legacy rpool/...
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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 ...
0
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0answers
49 views

ZFS Snapshots and low space on zpool

I am trying to backup every hour my zvols. I am using zfs for virtual servers on Proxmox VE. I made myself script, which runs snapshot every hour and then send it to offsite backup, then bookmarks ...
5
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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 ...
-1
votes
1answer
24 views

Physical Backup of Maria DB as a snapshot using LVM

I have a SQL database which I want to backup as a snapshot. I want to use LVM to do so, but I am not able to do it. Also my database is not stored in a LVM partition but its located in my /dev/sda2 ...
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
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
4answers
518 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 ...
2
votes
1answer
3k 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
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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 ...
4
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0answers
266 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 ...
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 ...
0
votes
1answer
91 views

How do backups that use LVM work?

Some LVM tutorials seem to claim that one take a snapshot of a logical volume (LV), then backup the snapshot using another tool, then remove the snapshot. When the unspeakable happens, the user can ...
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
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 ...
0
votes
1answer
133 views

Snaphot for backup changing files with rsync?

With rsync, is it acceptable to modify some files in a file system, while backing up the file system? If yes, is it necessary to take a snapshot before backup, and do an incremental backup after ...
1
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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
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0answers
592 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 ...
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 ...
1
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0answers
397 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 ...
2
votes
0answers
197 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
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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 ...
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

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 ...
9
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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 ...
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 ...
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 ...
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 ...
1
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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 / ...
8
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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-...
1
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0answers
139 views

bad inodes reappear after fsck() for vps guests

I have several vps guests that were created by virt-resize. I do daily backups on the guests by creating a snapshot and rsync file contents. But some of them don't have a clean disk image. As soon as ...
1
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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?
0
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1answer
296 views

LVM Snapshot without copy-on-write

I've been experimenting with LVM and how I can use it for managing data on my NFS server. With everything that I've read about snapshots, I am still unsure about how they perform in real life. Why ...
1
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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 ...