root%bostonu.csnet@CSNET-RELAY.ARPA (BostonU SysMgr) (10/27/85)
Not much, it just dumps out some of the info to aid in detective work. Mainly as a matter of personal experience I find that if two hosts won't talk to each other over an ethernet a good first thing to be able to check is whether or not they ARP'd, it just eliminates most of the networking software as the culprit (ARP is very simple and requires almost nothing much in the way of software to be configured right except that the two hosts agree on the other's IP address as specified in /etc/hosts and that the same ethernet is to be used.) If they won't ARP and the tables look right, and an ifconfig and/or netstat and/or telnet-to-a-working-host seems right, then I can concentrate on the hardware. If you ARP'd in the recent past and the right stuff is in the ARP table, then the hardware was obviously working in the recent past so either your problem is not hardware or very recently has become so (someone tripped over a transceiver cable or something.) It's just another little piece of information, the trick with debugging most anything is being able to peel away as much as you can first. You may need something else to solve your problem. Sorry. -Barry Shein, Boston University