[comp.protocols.tcp-ip] routing with virtual subnets

meggers@mothra.nts.uci.edu (Mark Eggers) (09/05/90)

I am working with a company that has a rather different short-term requirement.

The setup is as follows:



--------------- Sun ----------- cisco ----- (world)
 subnet a        |    subnet e
 subnet b        |
 subnet c        |
 subnet d        |
                 |
                 |
          slip to subnet f

Subnets b-d are 'virtual' subnets, existing on the same wire as subnet a.  I
can route between the subnets a-d by adding the following type of lines:

route add net.b.0 hostip 0

where hostip is the IP address of the host that the route is being added to.

Gated is running on the Sun, and announces subnets a-d, and f to the cisco.
However, I cannot route from subnets b-d to any other subnet on the other side
of the Sun, or through the cisco.

Any thoughts would be appreciated.

/mde/

satz@CISCO.COM (Greg Satz) (09/06/90)

All of the hosts on subnets a-d need to know about the overlayed scheme.
That is hosts on subnet b need to know that subnets a, c, and d also exist
on the same ethernet cable. The command that you used on your sun router to
inform it of the overlay is also necessary for those hosts on subnets b-d:

route add net.a.0 hostip 0
route add net.c.0 hostip 0
route add net.d.0 hostip 0

This is necessary for a host on subnet b.

Greg