I had this server for a month, and over the past month it's been steadily getting about 1000 megabytes of inbound traffic per day...

It is firewalled off so it does not reply or send anything out, it's not a web, or mail, or DNS server. It does not interract with public, and does not generate traffic. These inbound packets just come in on their own for some reason.

I assume this is something left over from the previous owner of the IP?

What are the packets doing exactly, are they just ARP replies or what?

Have you run tcpdump to see what's going on?

Id suspect its just someone probing for holes. I have a box running right now that really doesnt do much right now. It gets a bit of inbound traffic every now and then.

Massive shared vlan spewing out broadcast traffic? That'd have to be fairly large one to generate 1GB/day though....

Gotta love them worms :)

blaster, sasser etc etc. They scan non-stop along with noisey Windows boxes and game servers doing alot of broadcast traffic. If you can ask for a Private VLAN and you will only see the worms traffic and no broadcast noise.

Monitor the data via IPTRAF (logged on as root via ssh) and see what sort of data you see.