Small daisy chain network config

Hi, here's what I'm trying to do with Mandrake 10.1 community:

A <--> B <--> C <--> *internet*

I've got A talking to B and B talking to C. I can't ping C from A nor
vice versa.

I'd like to use MCC's network configuration tool but it seems to be
screwing things up a bit. For instance, I'm getting the host's
nickname on the same line as the localhost in /etc/hosts. Also, in
the past I've had, for instance, machine C define B as it's default
route when I'd rather have the internet be the default route. I've
had to go in by hand and delete that route and re-enter it to the
internet after connecting.

I'd really prefer to use webmin but something gave me the impression
that the settings in mcc seem to take preference over the webmin
settings (like they are not persistent after a reboot).

Ok, so if I try it from the command line I do something like:

(from A)

ifconfig eth0 a pointopoint b

route add -host c gw b

(from B)

ifconfig eth0 b pointopoint a

ifconfig eth1 b pointopoint c

(from C)

ifconfig eth0 c pointopoint b

route add -host a gw b

(end of example)

Sometimes, I am not able to get the pointopoint commands to take so I
have to do
something like:

(from b)
route add -host a eth0

I went into machine b with webmin and checked the box for it to act as
a router.
I even tried adding promisc to the ifconfigs of machine B. Still
nothing.

Can you think of anything I might be missing?

Also, how do you translate, for example the gateway designations into
the fields in mcc and/or webmin. It appears that the gateway route
designations would be done from A and C, however it appears that B is
where they would be entered in mcc or webmin.

Can anyone point to some better documentation for webmin and/or mcc
(or a good thread) that might be enlightening on this subject,

TIA,

-Kevin

Kevin Haddock wrote:

>Hi, here's what I'm trying to do with Mandrake 10.1 community:
>
>A <--> B <--> C <--> *internet*
>
>I've got A talking to B and B talking to C. I can't ping C from A nor
>vice versa.
>
>I'd like to use MCC's network configuration tool but it seems to be
>screwing things up a bit. For instance, I'm getting the host's
>nickname on the same line as the localhost in /etc/hosts. Also, in
>the past I've had, for instance, machine C define B as it's default
>route when I'd rather have the internet be the default route. I've
>had to go in by hand and delete that route and re-enter it to the
>internet after connecting.
>
>I'd really prefer to use webmin but something gave me the impression
>that the settings in mcc seem to take preference over the webmin
>settings (like they are not persistent after a reboot).
>
>Ok, so if I try it from the command line I do something like:
>
>(from A)
>
>ifconfig eth0 a pointopoint b
>
>route add -host c gw b
>
>(from B)
>
>ifconfig eth0 b pointopoint a
>
>ifconfig eth1 b pointopoint c
>
>(from C)
>
>ifconfig eth0 c pointopoint b
>
>route add -host a gw b
>
>(end of example)
>
>Sometimes, I am not able to get the pointopoint commands to take so I
>have to do
>something like:
>
>(from b)
>route add -host a eth0
>
>I went into machine b with webmin and checked the box for it to act as
>a router.
>I even tried adding promisc to the ifconfigs of machine B. Still
>nothing.
>
>Can you think of anything I might be missing?
>
>Also, how do you translate, for example the gateway designations into
>the fields in mcc and/or webmin. It appears that the gateway route
>designations would be done from A and C, however it appears that B is
>where they would be entered in mcc or webmin.
>
>Can anyone point to some better documentation for webmin and/or mcc
>(or a good thread) that might be enlightening on this subject,
>
>TIA,
>
>-Kevin
>
>
Hi Kevin,

I think the best way to learn is to fix something is understanding how
it works. Forget a moment about webmin or other tools and try to do it
by hand.
The "Rute" tutorial has a useful example:
http://www.icon.co.za/~psheer/book/node28.html.gz

If you are in a hurry, try the following:
On B: Check if routing is indeed enabled
cat /proc/sys/net/ipv4/ip_forward
This returns 1 if it routing is on, 0 if it's not.

On all machines: Monitor what's happening in the logs. Sometimes you
find out about errors or problems.
tail -f /var/log/messages
tail -f /var/log/syslog (in a second console)

Also, next time try to post more specific details. For example: the
results of running "ifconfig" and "route" on all machines, or the exact
commands that you typed and their output

Mihai