I've got one server in a DMZ which has limited access via SMB to another one in the internal network. A web server on that external machine needs access to a whole partition on that internal server.
I'm still using a quick and dirty solution. the web server still runs as a SYSTEM user. I managed to mount the share for that user.
The main problem: this setup is not reboot-safe. After a reboot the connection has to be re-established, because there's no way to save the credentials fot hat share.
P.s. the DMZ server is not in the windows domain