Thanks to all who responded to my query.
gutherz@prandtl.nas.nasa.gov
wallen%cogsci@ucsd.edu
rjt@eastrg1.cray.com
benny@DOUG.MED.UTAH.EDU
ucs.adelaide.edu.au!mrp@uunet.UU.NET
jan@eik.II.UIB.NO
swb@dainichi.tn.cornell.edu
jam@philabs.Philips.Com
earle@poseur.jpl.nasa.gov
You all said that the prudent thing to do was to use the same netmask
(255.255.255.0) on both sides of the gateways and subnet all of the machines
on the engineering 'backbone' this way too. Well this does work, but it just
won't do.
The remainder of our network here is 'flat'. That is to say, there is no
gateway between our 128.119.91 'net' and, for instance, the 128.119.41 'net'
or our gateway to the outside (128.119.1.1). If We use a Class C subnet mask
we will be able to see the machines behind the similarly subnetted gateways
but not several hundred other (more important) machines.
Also, at the risk of sounding obstinate, SunOS 4.0.X was supposed to support
different masks on a gateway (unlike 3.5 where they HAD to be the same). We
also choose not to use 'routed' because of the traffic and because previously
the only route any machine needed was a default route to our
gateway to the outside. Another problem with using a Class C netmask is that
there are many other machine that do not understand subnetting at all.
I think the solution is to do what we were doing but educate our off-campus
gateway about these subnets so that, once again, we will only need a single
default route.
I have enclosed my original posting below and thanks again to all who
responded. If anyone has any other ideas, I'm still willing to listen.
-Marc
----- Begin Included Message -----
We have a class B network and are using 128.119.91 as the Engineering network.
We have three subnets gatewayed to this network with 2 sun 3's and a microvax.
The gateways are all configured like this:
sim1# ifconfig ie0
ie0: flags=63<UP,BROADCAST,NOTRAILERS,RUNNING>
inet 128.119.87.1 netmask ffffff00 broadcast 128.119.87.255
sim1# ifconfig ie1
ie1: flags=63<UP,BROADCAST,NOTRAILERS,RUNNING>
inet 128.119.91.56 netmask ffff0000 broadcast 128.119.255.255
Machines on the 128.119.91 network are configured like this:
gumby{49}% ifconfig ie0
ie0: flags=63<UP,BROADCAST,NOTRAILERS,RUNNING>
inet 128.119.91.42 netmask ffff0000 broadcast 128.119.255.255
and have static routes that look like this in rc.local.
/usr/etc/route add mag-net mag-gw 1
/usr/etc/route add sim-net sim1-gw 1 #sim-net=128.119.87, sim1-gw=128.119.91.56
/usr/etc/route add pclab-net pclab-gw 1
The problem is that machines on the 128.119.91 network can only connect to the
subnet that is listed first when you do a netstat -r. Has anyone ever seen this
behavior before?
Thanks, Marc
----- End Included Message -----
This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:05:55 CDT