Solved...
Your comment about hard disc space made me wonder if maybe it could be some problem with the filesystem on the partition.
A quick sudo e2fsck -f /dev/scd1 found some corrupt inodes that were fixed and the problem went away.
All the virtual machines are running happily again, or so it seems.
Thanks for all your help, Serge.
Kind regards.
Solved...
Your comment about hard disc space made me wonder if maybe it could be some problem with the filesystem on the partition.
A quick sudo e2fsck -f /dev/scd1 found some corrupt inodes that were fixed and the problem went away.
All the virtual machines are running happily again, or so it seems.
Thanks for all your help, Serge.
Kind regards.