The net tile on the overview is one number for the whole machine. This table is each interface on its own.
Open the machine, then network › network. Under the address tiles, interfaces is every NIC the agent reported, busiest first. Receive and transmit are the rate since the last heartbeat. Accounts server has eth0 on 10.1.1.10 and eth1 on 10.1.2.10. Errors and drops are zero on both. The overview net tile is the sum of those rates.
Errors and drops are counters since the last heartbeat, not a lifetime total. The address tiles above this table are See how a machine is connected. Neighbours on the subnet are Read devices found on the LAN.