want to resume interrupted zfs send
With ZFS send/receive of large datasets, it would be rather nice to have an incremental or a resumable zfs send/receive system. in my current case, I have 50TiB uncompressed (which is how it's sent over the wire with zfs send/receive), so with the current hardware/compression/network bandwidth/etc, it'll take about two weeks to transfer it all. While time isn't a big issue in this, the chance of mbuffer/nc/whatever getting interrupted somehow is persistent. AFAICS the current code is somewhat incremental, in that it sends a snapshot at a time, and while this is good, it doesn't help much if the initial snapshot (after rotating them for a while, destroying old ones) contain 95% of the data.
So, would it be possible somehow to create a resumable snapshot transfer solution without rewriting zfs? Ideally, such a thing would allow for rebooting source and destination servers and not merely help stabilising the stream.
Updated by Michael Keller over 7 years ago
Isn't it possible to pause the pipe from zfs send by not reading anything from it and then later resume reading? The same for zfs receive?
If so a wrapper for the pipes will do (and how that exactly works is depended on the use case...).
The only case a zfs rewrite will be needed is if zfs send for the same snapshots will output every time different byte streams. In such a case a "resume" by skipping already captured output won't work if the system restarted while zfs send was paused.
Updated by Matthew Ahrens about 4 years ago
- Subject changed from Partial/incremental ZFS send/receive to want to resume interrupted zfs send
- Assignee changed from Christopher Siden to Matthew Ahrens
See also slides http://www.slideshare.net/MatthewAhrens/openzfs-send-and-receive
and video https://www.youtube.com/watch?v=iY44jPMvxog
for more details.
Updated by Electric Monk about 4 years ago
- Status changed from New to Closed
- % Done changed from 0 to 100
commit 9c3fd1216fa7fb02cfbc78a2518a686d54b48ab8 Author: Matthew Ahrens <firstname.lastname@example.org> Date: 2015-10-10T04:56:01.000Z 2605 want to resume interrupted zfs send Reviewed by: George Wilson <email@example.com> Reviewed by: Paul Dagnelie <firstname.lastname@example.org> Reviewed by: Richard Elling <Richard.Elling@RichardElling.com> Reviewed by: Xin Li <email@example.com> Reviewed by: Arne Jansen <firstname.lastname@example.org> Approved by: Dan McDonald <email@example.com>