trying to config an adsl interface for my O2 broadband

I'm in the UK and have an 8mb DSL servisc from O2, i'm trying to configure a wic1-adsl so that I can access my lab from the internet, this is as far as I have got with the config, i've got it to the point, with this config the interface moves from up to down periodically

config t
ip default-gateway 87.194.212.1

access-list 1 permit 10.0.0.0 0.0.0.255
ip nat inside source list 1 interface atm 0/0 overload

int atm 0/0
interface ATM0/2
ip address *.*.*.* 255.255.252.0
no shut
no atm ilmi-keepalive
dsl operating-mode auto
ip nat outside

int f0/0
ip address 10.0.0.1 255.255.255.0
no shut
ip nat inside

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Comments

networker050184

If you have a DSL router you should be able to plug the CAT5 into the fast ethernet port on your router. You also need to remove the ip default-gateway command and replace it with an default route (these two are NOT the same thing). Is your ip address from your provider static? If not you may also need to configure your outside interface for DHCP.

aueddonline

sorry this is the config the nat what configured wrong on the above ADSL configuration

config t
ip default-gateway 87.194.212.1

access-list 1 permit 10.0.0.0 0.0.0.255
ip nat inside source list 1 interface atm 0/2 overload

interface ATM0/2
ip address *.*.*.* 255.255.252.0
ip nat outside
ip virtual-reassembly
no shut
no atm ilmi-keepalive
dsl operating-mode auto

int f0/0
ip address 10.0.0.1 255.255.255.0
no shut
ip nat inside

aueddonline

yes it's a static address, i'd prefer the RJ 11 going straight into the cisco router,

aueddonline

where is the 'default route' command configured? it's not a command in the help menu in global or interface config mode

networker050184

ip route 0.0.0.0 0.0.0.0 (next hop or exit interface here). How did you make it through the CCNA with out knowing how to configure a default route?

I'm not familliar with connecting the home DSL line to a wic1-adsl, but you are more than likely going to need to configure a dialer interface. Sorry not much help on this never done it before.

aueddonline

I shouldn't think a dialer would need to be configured as it's an always on service, yeah a dumb moment then, can't be clever all the time

My service provider has actually given that default-gateway info in the welcome pack, so that's why I included that

Turgon

You may be wasting your time. From the looks of things you have been assigned one externally routable IP address and you are hiding everything on the LAN behind that address. How do you intend to be able to access home devices when you are using NAT overloading? I think you need static NAT and some more IPs from your provider.

dtlokee

If you know the port numbers for the connections you want you can use static PAT, for example RDP (TCP 3389)

ip nat inside source static tcp 10.1.1.5 3389 12.1.1.12 3389 extendable

then let's say you want another inside host to use RDP also, you can but you need to change the inside global port in use.

ip nat inside source static tcp 10.1.1.10 3389 12.1.1.12 3390 extendable

That is all there is to it. Whe nyou connect to the frst computer from outside, use the default port, to connect to the other computer use the port 3390.

If this is for telnet taffic you can do the same thing, just make sure the access server you are trying to connect to has a default route back to the router connected to the Internet.

Turgon

Yup.

That's an alternative approach if you are stuck with the one IP address but as dtlokee says you will need to use different ports so the router has a unique socket it can use to check which destination to hand the inbound connection to.

I recall using this a few years ago in a situation where I inherited a couple of webservers hidden by a single IP address. I had to use port 80 and port 81 for the inbound connections which was a bit of a drag for the enduser. If it's for your own personal use you should be fine, just make sure whatever application you intend to use for the connection is set up to use the appropriate port.

mikej412

Once you get it working, you could also use a VPN to gain access to your home lab.

This old thread on DLSReports may help you configure your WIC-1ADSL.

First big question (after why don't you just use a DSL Modem?) -- are you sure your ISP supports the WIC-1ADSL?

Second question -- router type? IOS Version and feature set?

aueddonline

cool i'll try this out sometime, i'm away from my lab for the next couple of days, so i'll try out some static pat when I can, thanks for your post, any other things about the configuration that need to be looked at?

aueddonline

i'm going to be using a 2610xm with an advanced security 12.4 IOS, I might end up using a standard router but it would be nice to get this wic adsl interface working nicely

as for the ISP i'd have to ring and ask I guess if it is compatible, whether I got an answer is another this all together

mikej412

You also might find something useful and/or more relevant on the Cisco Asymmetric Digital Subscriber Line (ADSL)
Configuration Examples and TechNotes web page.

Lots of good configuration examples here.

cambei

If O2 are following the same sort of standards as the rest of the country then you are looking at a PPPoA based connection, VPI/VCI 0/38 and the modulation type of G.DMT.

For the DSL connection you need either a dialer interface or a virtual interface.

I work in tech support (for 2 more days then moving up in the world

) for a UK ISP and a common problem that cuases 5 minute sessions is if the modulation is set to the American version as the standards are close enough to work but the errors stack up on the line quickly so the connection drops and re-establishes itself. The correct standard should be ITU G.992.1 (G.DMT) Annex A or G.DMT. To set this, use the command "dsl operating-mode itu-dmt" in the ATM interface configuration mode.

Here's my working example on a 2621, it works fine and I have had no issues apart from some crazy SNR values which were reported.

Most relevant bits:

!
ip name-server 217.169.20.20
ip name-server 217.169.20.21
!
interface ATM0/1
 no ip address
 no atm ilmi-keepalive
 dsl operating-mode auto 
!         
interface ATM0/1.1 point-to-point
 pvc 0/38 
  encapsulation aal5mux ppp dialer
  dialer pool-member 1
 !

interface Dialer0
 ip address negotiated
 ip access-group WAN_INBOUND in
 no ip proxy-arp
 ip nat outside
 ip virtual-reassembly
 encapsulation ppp
 dialer pool 1
 ppp authentication chap callin
 ppp chap hostname ***** ISP USERNAME *****
 ppp chap password ***** OUTPUT REMOVED *****
!
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer0
ip route 81.187.55.32 255.255.255.224 81.187.22.186
!
no ip http server
no ip http secure-server
ip nat source list PRIVATE_NAT_RANGE interface Dialer0 overload
ip nat inside source list PRIVATE_NAT_RANGE interface Dialer0 overload

I hope something in here helps.

nel

I work in tech support (for 2 more days then moving up in the world icon_smile.gif ) for a UK ISP and a common problem that cuases 5 minute sessions is if the modulation is set to the American version as the standards are close enough to work but the errors stack up on the line quickly so the connection drops and re-establishes itself. The correct standard should be ITU G.992.1 (G.DMT) Annex A or G.DMT. To set this, use the command "dsl operating-mode itu-dmt" in the ATM interface configuration mode.

Is this why my adsl is absolute rubbish by any chance?

cambei

nel wrote:

I work in tech support (for 2 more days then moving up in the world icon_smile.gif ) for a UK ISP and a common problem that cuases 5 minute sessions is if the modulation is set to the American version as the standards are close enough to work but the errors stack up on the line quickly so the connection drops and re-establishes itself. The correct standard should be ITU G.992.1 (G.DMT) Annex A or G.DMT. To set this, use the command "dsl operating-mode itu-dmt" in the ATM interface configuration mode.

Is this why my adsl is absolute rubbish by any chance?

Possibly. How long is a piece of string? :P

When you say your connection is rubbish, is it intermittently connecting? Are there speed issues? Does the PPP session stay up but there is high packet loss or no throughput?

There is a lot of things to take into account with ADSL unfortunately. Basic routine for diagnostics would involve:
* Connect the router to the master test socket if available or else the master phone socket
* Disconnect all other devices from the line
* Try an alternative micro-filter
* Check the phone lines for crackling, noise, echoing etc - if there is, report it to your phone provider
* Check for outside sources of interference - common seasonal problem is christmas tree lights

If all of the above things don't resolve the issue, it __COULD__ be a problem with the line or the DSLAM line card or port etc and it would be worth speaking to you ISP tech support. If you want anymore advice feel free to PM me, but I'd rather not proceed to hijack this thread.

mikej412

cambei wrote:

I'd rather not proceed to hijack this thread.

With good posts like that... hijack away!

Plus it's "close enough" and relevant enough to be on-topic.

nel

Well, dont mind if i do!

basically the connection just drops every 10 mins roughly. ive done most things you've posted. its like the connection times out and it always has to reconnect. this can be when downloading or to just general web surfin. it drives me crazy. you ring the provider and you get the usual "Well your line has tested fine on our end" stuff.

i have to say, ive had both cable and adsl and boy it seemed like the cable whipped adsl's ass for everything! i have had countless issues with adsl where cable was the Rambo of the connection world haha, roll on rambo 4! booya!

cambei

Lol.

In MY oppinion, ADSL is inferior to cable in terms of stability and speed, practically at least (and in the UK). The thing with cable in the UK is that the infrastructure, mostly the cabling, is so much newer and fit for purpose. Parts of the country's PSTN lines are still Victorian! Or at least that's why I have heard.

The other BIG advantage of cable in the UK is that it is not always sold as a wires-only service like ADSL, meaning there are less issues caused by poor customer setup or conditions.

If you want to PM me nel and let me know the provider etc I could TRY and help you out. Some ideas that come to mind would be enabling your router (I am making assumptions now :P ) to respond to ICMP echo's so that we could monitor for packet loss etc. Also depending on the router, we may be able to see a cause (ie. I have seen some routers that have the idle-timeout disabled in the web-interface but it still appears to be enabled and a factory reset of the router has solved this).

One thing with Service Providers and faults is that it is in their best interests to pass blame to your end. However, a decent support department will rule things out at your end and make an informed decision and respect your wishes if you believe the fault to be outside of your control.

One thing I forgot was trying an alternative ADSL router/modem on the line or trying this equipment on another line and see if the problem persists. If either of these is not possible, a factory reset of the eqipment can solve a handful of issues, especially with SOHO style routers.