Linksys Router

I have a Linksys router RTP300. Doing NAT to a Lan.

I have linux servers on the Lan side. The servers are scratch built Linux
boxen. All hosts are Linux boxen no ms windows (not on my network)

Is there a way to get the ip address (internet side) without logging in to
the administration setup?

Arp will only get me the address on the Lan side and not the Internet
side (That is I don't know how to ask it to get me what I am looking
for).

I need to detect when my ISP changes my dynamic ip (ip doesn't change very
much).

I am trying to run ddclient from a server on the LAN to update DNS to
DynDNS.org (a dynamic dns provider).

I know I can put the server directly on then internet (DMZ) side but I want
to avoid that. I want to port forward port 80 from the linksys to the
webserver on the LAN side to take advanage of the firewall in the linksys
router (yes the server has its on iptables firewall).

Thanks for any ideas/help/suggestions you may have.

--
Dancin' in the ruins tonight
Tayo'y Mga Pinoy

On 2006-09-19, Baho Utot <baho-(E-Mail Removed)> wrote:
> I have a Linksys router RTP300. Doing NAT to a Lan.
>
> I have linux servers on the Lan side. The servers are scratch built Linux
> boxen. All hosts are Linux boxen no ms windows (not on my network)
>
> Is there a way to get the ip address (internet side) without logging in to
> the administration setup?

Does the Linksys support sshd? If so, configure that and run ifconfig.
(Or, if you're able, install openwrt on it, which will definitely
support ifconfig.)

If not, you can still script logging in to the admin web interface and
parse out the IP. Perl has a bunch of modules to help do that.

--keith

--
kkeller-(E-Mail Removed)
(try just my userid to email me)
AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
see X- headers for PGP signature information

Hi,

This answer i gave you assuming there is snmp enabled on the router

as you said on the LAN there are all the Linux boxes and also i assume
that they have the snmpwalk utility.

you execute the command

root$ snmpwalk -v1 -c public <host ip address> 1.3.6.1.2.1.4.20.1.1

This command will give you the list of ip address the device have so if
you exclude the LAN IP address and loopback address the other ip
address is ur WAN ip address.

bye,
sunil
Keith Keller wrote:
> On 2006-09-19, Baho Utot <baho-(E-Mail Removed)> wrote:
> > I have a Linksys router RTP300. Doing NAT to a Lan.
> >
> > I have linux servers on the Lan side. The servers are scratch built Linux
> > boxen. All hosts are Linux boxen no ms windows (not on my network)
> >
> > Is there a way to get the ip address (internet side) without logging in to
> > the administration setup?
>
> Does the Linksys support sshd? If so, configure that and run ifconfig.
> (Or, if you're able, install openwrt on it, which will definitely
> support ifconfig.)
>
> If not, you can still script logging in to the admin web interface and
> parse out the IP. Perl has a bunch of modules to help do that.
>
> --keith
>
> --
> kkeller-(E-Mail Removed)
> (try just my userid to email me)
> AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
> see X- headers for PGP signature information

(E-Mail Removed) wrote:

>
>
> Hi,
>
> This answer i gave you assuming there is snmp enabled on the router
>
> as you said on the LAN there are all the Linux boxes and also i assume
> that they have the snmpwalk utility.
>
> you execute the command
>
> root$ snmpwalk -v1 -c public <host ip address> 1.3.6.1.2.1.4.20.1.1
>
> This command will give you the list of ip address the device have so if
> you exclude the LAN IP address and loopback address the other ip
> address is ur WAN ip address.
>
> bye,

I'll look into that Thanks

--
Dancin' in the ruins tonight
Tayo'y Mga Pinoy

Keith Keller wrote:

>
>
> On 2006-09-19, Baho Utot <baho-(E-Mail Removed)> wrote:
>> I have a Linksys router RTP300. Doing NAT to a Lan.
>>
>> I have linux servers on the Lan side. The servers are scratch built Linux
>> boxen. All hosts are Linux boxen no ms windows (not on my network)
>>
>> Is there a way to get the ip address (internet side) without logging in
>> to the administration setup?
>
> Does the Linksys support sshd? If so, configure that and run ifconfig.
> (Or, if you're able, install openwrt on it, which will definitely
> support ifconfig.)

Yes it does have secure shell (sshd). I will try the ifconig and see what
happens

>
> If not, you can still script logging in to the admin web interface and
> parse out the IP. Perl has a bunch of modules to help do that.
>
> --keith
>

Yes I thought about checkip.dyndns.org and either scraping it or knitting a
few perls together

I was trying not to go that route, but I think it will be the most
productive one.

Thanks


--
Dancin' in the ruins tonight
Tayo'y Mga Pinoy