dennis@gandalf.nosc.mil (Dennis Cottel) (08/15/88)
> Do multiply gateways work with TCP_BSD 3.1? If one of the gateways > goes down, should the users notice or will they continue to work on the > next available gateway? I have been trying to set up a redundant gateway. Here's what I've found so far. We are running SR9.7 with TCP 3.1beta. On one ring of 32 nodes, we have one gateway in a DSP80A and another in a DN3000, both talking via the same Ethernet to a bunch of VAXes running BSD4.3 UNIX. We are not running routed, just using the static tables in local.txt. A node will initially send packets out through the first gateway in the local.txt list. If the server on this gateway goes away, the next TCP application (telnet, rsh, etc.) will find the second gateway and send packets out there. At this point the order of the gateways as reported by "tcpstat -g" will change with the functioning gateway now first. Even after the original gateway is again available, the second continues to be used. I would prefer to tag the first as the "primary" gateway so that I could control where the main server load is performed. The switchover is not transparent to an application session. An rlogin, for instance, dies and has to be restarted. Therefore, the Apollo side of this is just about right. Unfortunately, our BSD VAXes are not smart enough to use an alternate gateway -- they insist on sending packets back to the Apollos through only one of the gateways. Therefore, the whole scheme is currently a failure. ;-( Actually, I've made it worse because I now have *two* nodes which can take down Ethernet communications! Dennis Cottel Naval Ocean Systems Center, San Diego, CA 92152 (619) 553-1645 dennis@NOSC.MIL sdcsvax!noscvax!dennis
krowitz@RICHTER.MIT.EDU (David Krowitz) (08/16/88)
Are your Vaxes BSD4.2 or 4.3? I thought that the 4.3 implementation handled subnetting, which should remove the restriction on using a single gateway via the "route add default" command. -- David Krowitz krowitz@richter.mit.edu (18.83.0.109) krowitz%richter@eddie.mit.edu krowitz%richter@athena.mit.edu krowitz%richter.mit.edu@mitvma.bitnet (in order of decreasing preference)