PPPoE on MX in a MPLS network

[ozgurguler]

We have a DSL modem which is providing access to our MPLS service. When DSL modem is in bridge mode and connected to MX67 internet port with PPPoE enabled, it cannot get IP address. When we plug in a windows pc with pppoe enabled instead of MX, it gets IP address. When we plug the same MX behind another bridge mode modem which is directly connected to internet, MX can get IP address without any issue. Is there a trick to make MX get IP with PPPoE when it is a MPLS network?

[DarrenOC]

Hi @ozgurguler 

Are you setting up the pppoe via the device  local status page

https://documentation.meraki.com/General_Administration/Other_Topics/Support_for_PPPoE_on_Cisco_Mera...

[ozgurguler]

Yes, via local status page. Because it is the only uplink, device is offline in dashboard

[DarrenOC]

What if you set the IP statically instead of Dynamic? 

[ozgurguler]

Yes tried it too. But it does not become online. I checked upstream devices if i see any packet from MX. There was nothing. 

[DarrenOC]

Hi @ozgurguler , came across this from another forum. Looks like the user found a workaround to the issue:

https://www.reddit.com/r/meraki/comments/67ucln/mx_with_pppoe_and_private_networks/?utm_source=amp&u...

Worth reaching out to Meraki support at this point.

[ozgurguler · Accepted solution]

I solved it. ISP was not sending a proper DNS IP, that's why interface was not able to reach cloud and become online. I called Meraki support and requested them to override ISP's blank DNS setting to 8.8.8.8. It worked. 

[DarrenOC]

well done. Glad the issue got resolved. So I take it the ISPs DNS weren’t able to resolve anything to allow the device to speak upto the cloud.