I am having issues with reliably exporting LXC containers to tarballs.
LXD/LXC version: 4.0.6
Installed via: snap
Host OS: Ubuntu 20.04
File system: ZFS
The error is always of this form:
ubuntu@lxc-host-r2:~/export$ lxc stop container ubuntu@lxc-host-r2:~/export$ lxc export container container.tar Error: Create backup: Backup create: Error adding "/var/snap/lxd/common/lxd/storage-pools/zfspool/backup.501085870/rootfs/home/ubuntu/random-file" as "backup/container/rootfs/home/ubuntu/random-file" to tarball: Failed to copy file content "/var/snap/lxd/common/lxd/storage-pools/zfspool/backup.501085870/rootfs/home/ubuntu/random-file": io: read/write on closed pipe
random-file here is a stand-in name for a file in the container’s file system. Exporting fails at a different file each time. Looking inside the containers, there is really nothing special about the files. They are all owned by a regular system user (“ubuntu” typically), are not corrupted, or otherwise conspicuous.
There is plenty of disk space available at the destination directory (also ZFS).
Any ideas what could be the source of the error?