Cisco 857 adsl connection problems

[kayasaman]

Hi guys, first up I would like to say thanks for sorting out my dhcp issues in the getting started with LANS part of the forum!

I have an issue now with my adsl connection. I have set up the dialer 0 and atm 0 interfaces according to this guide:

http://www.cisco.com/en/US/tech/tk175/tk15/technologies_configuration_example09186a008071a601.shtml

and have supplied my ISP settings:

VPI 0

VCI 38

Encapsulation VC/MUX or VC Based

Protocol PPPoA

Mode G.DMT

Authentication CHAP

Preferred MTU 1500 (or as close to as possible)

I have supplied my config as txt file.

Again I'm very new to Cisco so please take things step by step.

Many thanks!

[paolo bevilacqua]

Hi,

please configure:

interface BVI1

ip nat inside

no ip nat pool pool2 200.200.100.0 200.200.200.0 netmask 0.0.0.255

no ip nat pool pool1 192.168.1.0 192.168.2.0 netmask 0.0.0.255

no ip nat source list 1 interface Dialer0 overload

no ip nat inside source list 1 pool no-overload

no ip route 0.0.0.0 0.0.0.0 ATM0

ip nat inside source list 1 interface Dialer0 overload

ip route 0.0.0.0 0.0.0.0 dialer1

After you have basic connectivity working please explain what do you want to achieve using nat pools and we can give you some configuration advice.

There are no whatsoever daemons to start in cisco IOS.

[kayasaman]

Wow, thanks alot I'm almost online! I can ping outside from the router :-)

Through the above config eveything is fine routerwise but I can't access the internet from my machines still - as you can see from the running-config the ethernet interface has been bridged with the wireless interface just to make things simple while I learn more about how to use the routers capabilities.

Basically what I would like to achieve right now is to be able to connect the 7 computers on my network to the internet and to each other via wireless interface, I have more plans for later but first I would just like to learn about my router so I will be ready when I come to make changes.

And by using nat pools I was just trying to follow the "basic setup" cisco documentation in order to get things working - without knowing how they work I guess!!

[paolo bevilacqua]

Hi, I don't think the radio interface supports routing, normally it's bridged to a bvi and you do routing from there.

Post again nat config.

[kayasaman]

Hi, here is new almost working running config.

[paolo bevilacqua]

Hi, as indicated previously,please configure:

ip nat inside source list 1 interface Dialer0 overload

[kayasaman]

hmm.... I thought I put the line in? Must have missed it!

Just entered it and tested from pc but still no luck :-( no url is resolving

[paolo bevilacqua]

Please configure correct dns server address under DHCP pool. You also do not need "import all".

[kayasaman]

Bingo I'm online!!! :-))

THANK YOU SO MUCH!

Something I'd like to understand though is that in the dhcp dns-server I put my isp's dns entry statically. Is there a way to make a dynamic dns resolution so that say if the dns server address changes the router will automatically change without me having to re-append the static config of each one of my computers?

[paolo bevilacqua]

Try removing the dns-server from dhcp poll. That should use the servers configured on the router. Then try removing them from configuration and to see if in fact these are passed by IPCP, this can be confirmed with "term mon" and "debug ppp negotiation".

[kayasaman]

I removed the dhcp dns-server but I had no luck in resolving dns.

I am connecting some of my machines via static ip and testing the internet through them at the moment. So if I put 62.xx.xx.203 in the static dns 1 entry with the dhcp dns server as the same number it works fine.

After removing the dns server from dhcp, I tried using 192.168.1.1 in the dns 1 entry, then I tried leaving it blank. Through both methods nothing resolved so I reverted back to the old config with dhcp dns server engaged.

Through my old routers I used to have 192.168.1.1 in the static dns 1 entry and every thing worked fine. This is kind of confusing as it leads me to believe that either the nat was translating the dns or they had a vlan in place.

Any thoughts?

[paolo bevilacqua]

Other routers do by default respond to dns queries to their address, by forwarding to real dns server.

Cisco doesn't do that unless you configure it.

It is not necessary because it works fine passing the real DNS server to clients. And if you want one that always works and it's easy to remember, try 4.2.2.1.

[kayasaman]

It's me being a beginer again but I didn't get the 4.2.2.1. Is that a default route between discovered dns from isp to dhcp dns or is it ip for dns once configured to relay from isp to host client?

Also do you know of any web articals or cisco pages that might help me better understand my router? I've downloaded loads of pdf's from cisco.com which are setup guides and howto's but I guess I need something that will teach me more about the way in which things can be done, rather then loose generic templates.

[andriyhar]

Try this one.

-------------------------------------

conf t

ip dhcp pool dpool1

no domain-name cisco.router

end

-------------------------------------

conf t

ip dhcp pool dpool1

no dns-server 192.168.1.1

end

-------------------------------------

conf t

ip dhcp pool pool1

default-router 192.168.1.1

dns-server REAL IP FROM INTERNET PROVIDER

lease infinite

-------------------------------------

conf t

no ip domain name cisco.router

end

--------------------------------------

conf t

ip nat inside source list 1 interface Dialer0 overload

end

---------------------------------------

conf t

access-list 1 permit 192.168.1.0 0.0.0.255

end

----------------------------------------

conf t

interface ATM0

no ip address

no ip redirects

no ip unreachables

no ip proxy-arp

ip route-cache flow

no atm ilmi-keepalive

dsl operating-mode auto

end

-----------------------------------------

conf t

interface ATM0.1 point-to-point

no snmp trap link-status

pvc 0/38

encapsulation aal5snap

protocol ppp dialer

dialer pool-member 1

end

[kayasaman]

Thanks!

I removed the dhcp dns-server and put the dns ip's from my isp into pc network config. All the old config from router is same though and seems to work fine.

[andriyhar]

Hi.

When you make change on router yours PC get connection automatic.