07-08-2011 01:11 AM
Hi All
I am working on a project in Saudi Arabia, and dealing with the local telco here, STC. We have bought from them a Ethernet to Ethernet 4MB link from Riyadh to Qassim.
On the Riyadh end they have presented a Cisco ME3400 and assigned us a Ethernet port on it. On the Qassim end they have presented a SDSL Thomson modem with an Ethernet port assigned on it. (I believe it is configured in 'bridge mode') In between Riyadh and Qassim is the STC MPLS cloud. The STC connectivity is as follows -
Riyadh end - Cisco ME3400 - Cisco 7609 (PE) - STC MPLS - Cisco 7609 (PE) - MSAN - Thomson SDSL Modem - Qassim end
My issue is that the Ethernet to Ethernet is not functioning as one Layer 2 broadcast domain, which is what we wanted to order. We are getting some strange inconsistent results. When I configure 2 Laptops in the same subnet, the two PCs ping fine. When I configure two cisco 2960 switches, back to back and configure an SVI with the same subnet on both ends, it fails to ping. When i configure a Cisco MWR2941 with SVI on both ends in the same subnet, ping works but has to be initiated from Qassim end. If line is idle, Riyadh end will not ping unless traffic is initiated from the Qassim end, where the SDSL modem is.
I spoke to STC engineer and he informed me that on the Qassim SDSL end we HAVE to have a Router and not a switch.According to the engineer the SDSL modem has to have a Router connected to it and not a switch. If i plug in a router, then this is clearly not a end to end Layer 2 braodcast domain.
Has anyone experience in this kind of setup. I am struggling to understand the STC engineers as their is a big issue with communication, the engineers don't speak good english.
Please can someone explain what they think is going on, and why I need a router to connect to the SDSL modem and not switch?
Kind Regards
Sid
07-09-2011 02:14 AM
Where have all the Experts gone?
07-09-2011 05:21 AM
Hi All,
I have attached a diagram showing what I am trying to achieve. The diagram attachement is above under the original post.
We would like to Carry a Dot1q trunk (multiple vlans) transparently over the STC EoMPLS point to point link as show in the diagram below. We want a flat Layer 2 LAN from end to end with the same IP subnets configured on Riyadh and Qassim VLANS.
As you can see in the diagram on both ends I have a dot1q trunk configured towards STC and vlan 100,200 and 300 allowed on the trunk. However I am not getting an end to end Layer 2 connectivity. For example Vlan 100 in Riyadh (192.168.1.1) is not pinging Vlan 100 in Qassim (192.168.1.2).
The only way I can get it to work or ping is Layer 3 to Layer 3, if I put a Laptop directly on both ends and configure IP on them in same subnet, only then it pings.
We raised a TAC case with the Service Provider and the engineer said on the Qassim end, we cannot connect a Switch directly to the SHDSL modem and we need to connect a Router to the SDSL modem. Is this correct and if so, what is the reason for this?
Also one thing we noticed is that Ping needs to be initiated from Qassim end. If we initiate ping from Riyadh it doesn’t work. I mentioned this to the STC engineer when I opened the TAC case and he asked me to configure SLA Monitor.
Side qaseem
Please put this code under physical interface
ip sla monitor 1
type echo protocol ipIcmpEcho STC_PE_IP_ADRESS
timeout 100
frequency 1
ip sla monitor schedule 1 life forever start-time now
Obviously this is not correct as the link should be constantly up and pingable, and should not need to be initiated from one end.
Please advise, what do you think it happening and what do I neeed to tell the Service provider?
Thanks in advance...
07-14-2011 05:47 AM
What is your Cisco Case ID ?
Do you configure dot1q subinterface when you connect the router at both ends ??
I believe its a simple L2 Circuit, you cannot send tagged traffic towards Service Provider, you need to confirm it from your SP.
07-22-2011 03:18 AM
Hi Yasir
Thanks, I was reading the document Ethernet access for NGN Metro networks and it was mentioning that there are two types of handoffs - simple and trunked.
The provider have given us a simple handoff with a SDSL modem on one end and the other end is trunked handoff with a Metro Switch.
Can you please clarify to me - is it possible to somehow do Do1q trunking from end to end in this setup, so I can transport multiple vlans over the setup.
I have asked the SP to replace the SDSL modem with a Metro switch solution so we have a trunked handoff on both ends. They are in the process of doing this and will take a week, but I am just curious if I could have got it to work in the setup they provided us before...
08-04-2011 06:10 AM
I dont think if RFC 1483 can do L2 Trunking, not easy in your scenario.
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