I have several legacy FreeBSD VMs made by ex-sysadmin who did some strange trick to save hypervisor storage space: he installed one VM from iso, the set it up a bit, installed needed software, then deleted ports tree and all package management related dirs (so basically the VM was stripped down for 1-2 Gb), then cloned this VM and changed some settings as needed.
Now as software versions become older and security updates should be considered I face the problem I simple can not do anything to these VMs.
No documentation left, nor this person is known to understand FreeBSD in depth so I doubt he did surgery-like thin work while deleting dirs - at least, no pkg or freebsd-upgrade cam handle the missing parts of filesystem.
Is there any way to run iso as “install upgrade” mode (like Windows installer can be used) so the FreeBSD installed fix the missing files?
P.S. I can only think of setting the same VM from scratch and copy configs from that “stripped” VMs but this quite time-consuming approach, so maybe it can be fixed with different approach?