LXC Copy Ignore Errors

gaia · December 13, 2021, 11:39pm

When copying a container with

lxc copy demo-container node4: --stateless --no-profiles --instance-only -s ssd

i get

Failed instance creation: Error transferring instance data: Rsync send failed: demo-container, /var/snap/lxd/common/lxd/storage-pools/default/containers/cdemo-container/: [exit status 24 read unix @lxd/ce8bdca1-4c47-49d8-aff8-278cb5ebc919->@: use of closed network connection] (file has vanished

because as expected files are being written and deleted constantly. i do not expect a consistent copy, but the good news is that the part that is constantly changing is “self healing”, so it gets rebuilt when missing/corrupt.

with this in mind, is it possible to have the instance be created, in other words, ignore any file errors? I know that standard rsync ignores these errors when copying.

tomp · December 14, 2021, 9:09am

What storage pool driver are you using for source and destination?

gaia · December 14, 2021, 10:44pm

It’s all dir. I need max performance from the disks (NVME Gen 4 BTW) and anything else was unacceptable.

tomp · December 15, 2021, 9:44am

Best thing to do is to open an issue at https://github.com/lxc/lxd/issues to track whether we can change the behaviour. Thanks

gaia · December 16, 2021, 12:22am

github.com/lxc/lxd

Option to let rsync finish with errors if the operator desires

opened 12:22AM - 16 Dec 21 UTC

gaia

* Kernel version: 5.10.0-9-amd64 Debian (source)/5.4.0-89-generic Ubuntu (tar…get) * LXC version: 4.0.11 | 6.1.0 (both) * LXD version: 4.21 (source)/4.0.8 (target) * Storage backend in use: dir (both`are dir drivers on underlying LVM using an entire partition) # Issue description When copying a container with `lxc copy demo-container node4: --stateless --no-profiles --instance-only -s ssd` i get `Failed instance creation: Error transferring instance data: Rsync send failed: demo-container, /var/snap/lxd/common/lxd/storage-pools/default/containers/cdemo-container/: [exit status 24 read unix @lxd/ce8bdca1-4c47-49d8-aff8-278cb5ebc919->@: use of closed network connection] (file has vanished` because as expected files are being written and deleted constantly. i do not expect a consistent copy, but the good news is that the part that is constantly changing is “self healing”, so it gets rebuilt when missing/corrupt. with this in mind, is it possible to have the instance be created, in other words, ignore any file errors? I know that standard rsync ignores these errors when copying. # Resolution Have an option to let rsync finish with errors, if the operator desires. [see this forum issue](https://discuss.linuxcontainers.org/t/lxc-copy-ignore-errors/12900)

Thank you, Thomas.