Wrong ip from $4 within ip-up.local

Wrong ip from $4 within ip-up.local

Post by YML-HK-EDP/Wilson La » Sun, 31 Dec 1899 09:00:00

Hi Everybody,

I have setup a gateway in a remote site using diald to
connect to local isp on demand and making use of the
ip address from the isp to fire up ipfwadm rules to let
remote users access the internet. Once the ppp0 is up
the I email back the ip-address-from the isp to me.

I obtained isp-allocated ip address within ip-up.local by
$4 and make use of if to setup ipfwadm commands.

"Most of the time" it works but "sometimes" the ip address
from $4 is the local-host's ip and ipfwadm rules do not
work as what I expected.

I have extended the up-delay from 5 to 10 seconds, but still
cannot solve the problem.

Anybody has any suggestions?

Using: Linux 2.0.36 Redhat 5.2
           diald 0.16.5-201
           pppd 2.3 patch level 5
           ipfwadm 2.3.0-6

Wilson Lam


Wrong ip from $4 within ip-up.local

Post by James Carlso » Sun, 31 Dec 1899 09:00:00

> "Most of the time" it works but "sometimes" the ip address
> from $4 is the local-host's ip and ipfwadm rules do not
> work as what I expected.

What are your pppd options and what logs do you see when the problem

Are you specifying "noipdefault"?  If the peer is supplying your
address in all cases, then this should be used.


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I've got a box running Redhat 6.1 working as a gateway for our home network.
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Now, consider this situation: I've got a webcam running on one of my windows
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ipmasqadm portfw -a -P tcp -L xxx.xxx.xxx.xxx 9999 -R 8888

in my rc.local.

This works very well for people connecting in from outside - they'd use a
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but if I try and use that URL from inside the local network, it doesn't
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which is rather annoying as it makes it difficult to test things (I have to
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I'm fairly sure the problem isn't with the webcam software - I've had the
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