Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [snapshot]

195 questions
26
votes
3 answers

Practical 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 be in addition to my current off site backup…
StrongBad
  • 5,151
  • 9
  • 47
  • 73
23
votes
1 answer

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?
bRuta
  • 391
  • 2
  • 3
  • 6
19
votes
4 answers

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 (unmount the overlay and then merge) solutions. I have…
ejm
  • 521
  • 1
  • 4
  • 6
17
votes
1 answer

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 functionality for block devices - preferably with…
Ole Tange
  • 33,591
  • 31
  • 102
  • 198
16
votes
4 answers

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 of a fault occurs.) Then restore the system back…
bRuta
  • 391
  • 2
  • 3
  • 6
16
votes
1 answer

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 needs a system with ZFS on the other end. I want…
Martin Grohmann
  • 263
  • 1
  • 2
  • 5
12
votes
4 answers

`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 copying the hard links. That is all great, but the…
john-jones
  • 1,698
  • 4
  • 24
  • 38
12
votes
1 answer

ZFS on Linux send/receive resume on poor/bad ssh connection

I am using ZFS on Linux, and trying to setup remote replication. But I have bad ssh connection, and zfs send/receive over ssh restarts again. I know there is a issue on ZoL, but I don't know when it will be implemented, or a new stable release come.…
Ural
  • 486
  • 1
  • 5
  • 8
11
votes
2 answers

How to delete btrfs subvolumes with 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 /@apt-snapshot-2013-04-17_21:44:30 ID 272 gen 352 top level 5 path…
Cactus
  • 805
  • 3
  • 9
  • 18
11
votes
1 answer

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 there. Is there any problem using snapper to enable…
MountainX
  • 17,168
  • 59
  • 155
  • 264
10
votes
1 answer

Error creating snapshot: Operation not supported: internal snapshots of a VM with pflash based firmware are not supported

I'm using Arch Linux, both host and guest. For UEFI boot, I've installed edk2-ovmf and made the guest use the firmware /usr/share/edk2-ovmf/x64/OVMF_CODE.fd. I want to create snapshots of my VM but am getting the error: Error creating snapshot:…
ChocolateOverflow
  • 871
  • 1
  • 8
  • 21
10
votes
1 answer

Why does ZFS rollback destroy intermediate snapshots?

Having used btrfs before, I was surprised to find out that rolling back a snapshot in ZFS not only changes the “working set” of files, but also requires that any snapshots which are newer than the rollback target must be destroyed as well: zfs…
Socob
  • 331
  • 3
  • 12
10
votes
2 answers

Btrfs snapshot to non-btrfs disk. Encryption, read acess

I want to try Btrfs. I've already found that you can make a snapshot of a live system but there are a few thing I haven't found answers for. Well, as I understand a snapshot basically a full copy in archive form of some sort. So can I make a…
dmh84
  • 147
  • 2
  • 6
9
votes
1 answer

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-snapshot) volume: if I typically keep the…
user12810
9
votes
2 answers

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 top level 5 path __snapshot ID 259 gen 59802 top…
Falmarri
  • 12,897
  • 17
  • 58
  • 71
1
2 3
…
12 13