Maybe a dumb question, but why would this warrant an evacuation? I get that it’s contraband, but it’s drugs, not a weapon. Unless they thought since one disallowed thing made it’s way in that there could be other stuff (weapons) as well?
Edit: or maybe they thought it could be anthrax at first, which makes much more sense as to why they would evacuate
You can configure many routers to act as DNS servers, then advertise themselves to client devices as a DNS server (with a secondary like 8.8.8.8 or whatever). Then you can just use the hostname of the device you want to access and as long as your client device is using your router for DNS it will resolve correctly.
How specifically to set this up depends on your networking equipment