How do I subnet a class B network
John R. Morris
jmorris at mwunix.mitre.org
Sun Sep 2 05:54:58 AEST 1990
Hi; I am fairly new to Unix and Suns and the "Net" so please bear with me.
I have a couple questions about subnetting.
I have some 4/110s and one 4/280 which were on a class B network. The
4/280 now has two ethernet interfaces and I want to make it a router,
isolating all of my machines from the class B network. I can't seem to do
it correctly and Sun-support is not very fast/helpful answering questions.
So I found out that this net has thousands of sun-gurus...
Anyway,
-------| |---------
| |
| ---------- |
rest | | my
of ------|sun4/280|---------- little
world | | corner
B | ---------- | C
| |
-------| |---------
On the 4/280 (running Sun OS 4.1) can I do the following:?
ie0 (rest of world, Class B)
inet 128.29.22.1 netmask 255.255.0.0 broadcast 128.29.255.255
ie1 (my little corner, Class C?)
inet 128.29.22.7 netmask 255.255.255.0 broadcast 128.29.22.255
If not, why? Should I change the IP address on the class B side to
128.29.23.1 I'm told I should change the netmask to 255.255.255.0 on both
sides but I don't know why. Then, what should my routing look like? Why
is the following wrong?
Routing tables
Destination Gateway Flags Refcnt Use Interface
127.0.0.1 127.0.0.1 UH 1 26 lo0
default Outside gateway UG lots lots ie1
129.83.0.0 128.29.22.1 U 0 100 ie1
128.29.22.0 128.29.22.7 U 27 19396 ie0
128.29.0.0 128.29.22.1 U 0 2 ie1
Any response besides comments on my compentency would be very appreciated.
Thanks in advance
John Morris
PS. I'm jmorris at mwunix.mitre.org (if I need to add that).
More information about the Comp.sys.sun
mailing list