Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!gem.mps.ohio-state.edu!apple!agate!ucbvax!imf.unit.no!hanche From: hanche@imf.unit.no (Harald Hanche-Olsen) Newsgroups: comp.sys.apollo Subject: Re: Apollo ethernet routing Message-ID: Date: 17 Oct 89 16:36:39 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 42 The problems of David Hassel are having remind me of a similar problem of our own. What we have discovered is that, apparently, a bug in the Apollo networking software (tcpd?) does not allow you to communicate with a directly attached subnet. I don't know if the network at Brookhaven uses directly attached subnets, but ours does. We have a class B network (129.241.0.0) on which netmask 255.255.255.0 is used, so that host 129.241.x.y is on subnet x. Some subnets are directly attached to one big ethernet, while others are connected via gateways. To get to a directly attached host 129.241.x.y from another, 129.241.u.v, say, the standard trick is the following invocation, from the latter machine: route add 129.241.x.y 129.241.u.v 0 The magic is in the metric of 0, which announces that the machine is directly available. However, on our Apollos the above command causes the route to be added with a metric of 1, rendering this trick useless. In our case, the solution is to use netmask 255.255.0.0 and rely upon ugly tricks like proxy ARP (a service kindly provided to us by the local network management) to reach non-directly attached subnets. Maybe Hassel is running into the same kind of problem? As to his PS remark, I think I can explain why netmask 255.255.0.0 does not work for him: Then the sequence /etc/ifconfig dr0 134.88.14.1 ... /etc/ifconfig eth0 134.88.1.14 ... means that both interfaces are on the same network, which the networking software will (correctly) reject. Most likely, eth0 will be marked down as a result of these commands(?). If I have understood the problem correctly, there is only one solution, and that is to obtain a new network number (say, a class C one) to be used on the token ring, and then use netmask 255.255.0.0 on the ethernet side. Or, you can try to make Apollo fix the bug. Good luck... :-) PS. If there is no bug at all, I would be delighted to hear about it and how to add a route with metric 0. Or if there is a bug, maybe there is a fix for it? I am all ears... - Harald Hanche-Olsen The Norwegian Institute of Technology