Hi David,
the ffdc files are located at
/opt/IBM/WebSphere/AppServer/profiles/Dmgr01/logs/ffdc
but as Alexei says your issue is a host resolution problem, WAs can't register (open) the ports on your machine "david-virtual-machine" because it can't find the host.
you need to do a succesfull ping to david-virtual-machine putting it on host fileor registering in DNS server
regards,