When working with LXD containers across multiple hosts, especially in environments with restricted network access, standard container migration becomes non-trivial. The key challenge lies in properly exporting both container data and metadata while maintaining compatibility between LXD versions.

The correct workflow involves:

# First publish the container as an image
lxc publish container-name --alias temp-image

# Then export the image (this creates two files)
lxc image export temp-image

# Clean up temporary image
lxc image delete temp-image

The error metadata.yaml: Not found in archive typically occurs when:

• Exporting directly from container instead of published image
• Using older LXD versions (pre-2.0.2)
• Missing the metadata tarball during import

Here's the full working process between two hosts:

# On source host
lxc stop my-container
lxc publish my-container --alias migration-image
lxc image export migration-image
# This generates two files: 
# - meta-migration-image-XXXXXXXX.tar.xz
# - migration-image-XXXXXXXX.tar.xz

# Transfer both files to destination host (using scp/rsync/etc)
scp meta-migration-image-* root@remote:/tmp/
scp migration-image-* root@remote:/tmp/

# On destination host
lxc image import /tmp/meta-migration-image-XXX.tar.xz /tmp/migration-image-XXX.tar.xz --alias imported-container
lxc launch imported-container new-container-name

When hosts can't communicate directly:

1. Export to intermediate storage (USB drive, S3 bucket)
2. Use split file transfer with checksums
3. Verify image integrity before import:

sha256sum *.tar.xz > checksums.txt
# Transfer checksums file separately
# On destination:
sha256sum -c checksums.txt

Important version-specific behaviors:

When network allows direct communication:

# Add remote host
lxc remote add remote-host --password=XXX --accept-certificate

# Copy directly between hosts
lxc copy local:container-name remote-host:new-container-name

When working with LXD containers across multiple Ubuntu hosts with restricted network access, the standard approach involves creating container images and transferring them between systems. The key steps are:

# On source host
lxc stop my-container
lxc publish my-container --alias my-image
lxc image export my-image

The error tar: metadata.yaml: Not found in archive typically occurs when using older LXD versions (pre-2.0.8) or when the export process doesn't properly bundle all required components. Modern LXD versions generate two files:

• metadata.tar.xz - Container configuration
• rootfs.tar.xz - Actual filesystem

Here's the complete working solution:

# On source host
lxc stop my-container
lxc publish my-container --alias temp-image
lxc image export temp-image

# This creates two files:
# - aaf012...metadata.tar.xz
# - aaf012...rootfs.tar.xz

# Transfer both files to destination host via scp/rsync
scp aaf012*.tar.xz user@remote:/tmp/

# On destination host
lxc image import /tmp/aaf012...metadata.tar.xz /tmp/aaf012...rootfs.tar.xz --alias imported-image
lxc launch imported-image new-container

For hosts with direct network access, configure remotes:

# On source host
lxc remote add remote-host  --accept-certificate --password=

# Copy image directly
lxc image copy local:my-image remote-host: --alias copied-image

# On destination host
lxc launch remote-host:copied-image new-container

If you encounter problems:

1. Verify LXD versions match (minimum 2.0.8 recommended)
2. Check disk space in /var/lib/lxd
3. Ensure proper permissions on transferred files
4. For custom images, include all dependencies

Remember that published containers become immutable images. Any changes require republishing the updated container.