Path: utzoo!attcan!uunet!husc6!bloom-beacon!apple!bionet!agate!ucbvax!WSMR-SIMTEL20.ARMY.MIL!WANCHO From: WANCHO@WSMR-SIMTEL20.ARMY.MIL ("Frank J. Wancho") Newsgroups: comp.protocols.tcp-ip Subject: Network Connectivity - Part 2 Message-ID: Date: 4 Nov 88 17:28:00 GMT References: Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 17 Clive, I discovered the same problem last night caused by the fact that the prime gateways were down (either deliberately taken down, looped off the net or powered down by the NOC) in an effort to compartmentalize the spread of the worm (not virus). It is not just the TOPS20 hosts which depend on these gateways for ICMP REDIRECTs - all hosts using the prime gateways do. Once I added a couple of other gateways, everything started flowing again everywhere except across the MIL-ARPA gateways (as I believe was the intent in shutting off those gateways). The lesson to be learned from this is that we should have at least one other non-MIL-ARPA prime gateway in the list of assigned gateways should it become necessary to isolate those two nets from each other in the future. --Frank