After a few other issues, I'm now running as root, I've enjoyed the confusion of watching my xcp-ng controller try and unmount my / partition and I'm trying to get backups working.
No errors in the command line:
2021-02-19T11:50:26.905Z xo:main INFO + WebSocket connection (::ffff:172.16.32.167)
2021-02-19T11:50:55.654Z xo:xapi DEBUG Snapshotting VM wpwtj as [XO Backup barber backup test] wpwtj
2021-02-19T11:51:03.693Z xo:xapi DEBUG exporting VDI wpwtj
but the web interface gives the following:
Error: The "path" argument must be of type string. Received an instance of IncomingMessage
This is node 12 straight from the nodesource repos, yarn run v1.22.10 straight from their repos, and latest XO from the vates repos - on Ubuntu 12.04 with latest patches. Hosts are running XCP-ng 8.2LTS also with the latest patches.
I've been accessing XO through an nginx reverse proxy (nginx 18, straight from their repos), but in order to reduce possible failure points I'm now connecting directly to the xo web interface with no tls, running on port 2080. The backup is the first of a backup of type Delta, VM manually selected, to an NFS remote. The same remote is working fine for a metadata backup.
As an experiment, I tried switching from a Delta Backup to a Backup, which changed the error to:
Error: The "path" argument must be of type string. Received an instance of Transform
Many thanks to all!