DHCP through DSLAM Huawei MA5300

[Youenn Rivoallan]

Hi,

I have a Cisco Router 877 connected by the ADSL interface to a Huawei MA5300 DSLAM on the adsl 0/0/1 interface.

On the other and, I have a isc-dhcp-server connected to the DSLAM on ethernet 7/2/3.

Both adsl 0/0/1 and ethernet 7/2/3 are part of the smartVLAN101 on the DSLAM.

adsl0/0/1 is configured as a downport and eth7/2/3 as the upport.

smartVLAN101 IP: 10.1.1.254 /24

DHCP IP : 10.1.1.253 /24

When I give the router a static address such as 10.1.1.1 it can ping VLAN101 at 10.1.1.254 and the DHCP at 10.1.1.253.

I would like the router to get an IP address from the DHCP.

You will find attached,

- a drawing of the actual layout

- the router 877 running-config

- the DSLAM MA5300 running-config

- the DHCP config

- the debug DHCP output of the router

- the output of the show DHCP-server 1 command on the DSLAM

As you can see, the router seems to send DHCP request through the right interface (ATM0) but the DSLAM do not receive them.

I've tried a lot of configurations based on what I found on the internet but none of them did the trick. So I decided to start back from this pretty basic config.

Any help would be much appreciated.

Regards.

[Georg Pauwen]

Hello,

on the Cisco, try to add the following:

ip forward-protocol udp bootpc

ip forward-protocol udp bootps

service dhcp

I'll have a look at the Huawei...

[Youenn Rivoallan]

Hello Georg,

Thank you for your answer,

I will try that tomorrow and let you know as soon as possible.

Regards.

[Youenn Rivoallan]

Hello,

I'v tried the commands that you suggested, unfortunately nothing changed.

I still have the same DHCP debug on the router and still no paquets received on the DSLAM.

Any other ideas ?

Regards.

[Georg Pauwen]

Hello,

on the Huawei, it looks like you have option 82 enabled, can you try and disable that ?

[Youenn Rivoallan]

Hi,

Option82 is disabled, no changes.

Tomorrow I'll try to create a sub-interface ATM because ATM0 is not point-to-point from what I've read here.

I'll let you know.

Thank you for your time Georg.

[Youenn Rivoallan]

Hi,

I have configured an ATM0.1 point-to-point interface and added some ACLs on the router and on the adsl interface of the DSLAM. Still no DHCPREQUESTS received on the DSLAM.

So I decided to create a virtual interface Dialer0 but it still does not work and I have the same DHCP debug on the router exept that the broadcast is sent to Dialer0 and not ATM0 or ATM0.1 anymore.

I can post the ACL that I added if you want.

Those were my last ideas to make this work, I don't really know what to try now.

Any ideas would be welcomed ...

[Georg Pauwen]

Hello,

on the 877, try and globally configure:

service dhcp

Does that make a difference ?

[Youenn Rivoallan]

Hello,

What do you mean by "globally configure" ?

I did run this command in configuration mode but it did not work.

[Youenn Rivoallan]

Hi,

I used a pppoe server to get dynamic IP address.

Here is the link to the post : https://supportforums.cisco.com/discussion/13304601/ppp-over-atm-not-working-cisco-877

Problem solved.