Solved

need to make a layer 2 network over Frame relay with Cisco

Posted on 2001-06-11
11
261 Views
Last Modified: 2011-09-20
Here is the situation. I have a customer with a bunch of connections. Some of the connections are ethernet over fiber. They all bridge together and we provide a layer 2 network between the customer's various sites.

We are now adding an additional few sites. But the new sites are going to connect with Frame relay.

I have 1 frame connection at my central site ( from which the fiber goes out) and 2 other sites that connect to the cloud. In addition, one of the 2 sites has a P2P T-1 going to a third site. Ideally I would like to continue to provide a layer 2 solution. I would have to guess I can use IP un-numbered on all my routers. But then how can I manage them? ideas?

I already have 3 2511s I can use and a 1600, so I think I am set on the hardware.



picture:

POP     ------ Cloud ------ site 1
                  |
                  |
                site 2 ---T1-- site 3
             
0
Comment
Question by:jjeff1
11 Comments
 
LVL 11

Expert Comment

by:geoffryn
ID: 6178096
Layer 2? So you want to bridge all of the sites togather?  Why is a layer 2 solution the best?  You will be wasting valuable WAN bandwidth on broadcast traffic.  
0
 
LVL 7

Author Comment

by:jjeff1
ID: 6178371
I am well aware of the waste of bandwidth. The point is that as an ISP I don't want to get involved in trying to deal with the customers IP addressing scheme.
0
 
LVL 1

Expert Comment

by:asarluhi
ID: 6179178
You can run the frame-relay interface as part of a bridge group.  Broadcasts are supported on multipoint interfaces with the frame-relay map bridge command.  See the following URL for more information:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/ibm_c/bcprt1/bctb.htm#xtocid1230316

This is technically an example for IBM transparent bridging, but it basically holds for any L2 protocol.  Remember to *not* configure IP addresses on the transit interfaces...

Let me know if you need more detail.

Good luck-
0
 
LVL 7

Author Comment

by:jjeff1
ID: 6179350
Yes, I was looking also for some basic config.

Also, would I by able to access these devices in any way? You said I can't assign an IP to the transit ( umm, you mean the serial interfaces )so I assume not.

0
 
LVL 79

Expert Comment

by:lrmoore
ID: 6179406
You have a couple of options:
at Site one, you can setup one interface with frame-relay encapsulation and run multiple sub-interfaces to the other sites. Each sub-interface can have it's own IP address. If you use IP unnumbered, then you can still manage the devices by connecting to whatever address you identify in the ip unnumbered statement.

Example:

Site 1 main:
  Interface Serial 0/0
   encap frame-relay
  Int serial 0/0.1
   description connected to site 2
   ip add 192.168.255.1 255.255.255.252
   frame-relay interface-dlci 200 {DLCI is assigned by the telco}
!
ip route <ip network of site 3> mask 192.168.255.2

Site 2
 
  Interface Serial 0
   encap frame-relay
  Int serial 0.1
   description connected to site 1
   ip add 192.168.255.2 255.255.255.252
   frame-relay interface-dlci 100 {DLCI is assigned by the telco}
!
  Interface serial 1
  description point-to-point to site 3
   ip address 192.168.255.5 255.255.255.252
!
ip route <ip network of site 1> mask 192.168.255.1
ip route <ip network of site 3> mask 192.168.255.6

Site 3:
 Interface Serial 0
 description point-to-point to site 2
 ip address 192.168.255.6 255.255.255.252
!
ip route 0.0.0.0 0.0.0.0 192.168.255.5

Hope this helps!
0
Control application downtime with dependency maps

Visualize the interdependencies between application components better with Applications Manager's automated application discovery and dependency mapping feature. Resolve performance issues faster by quickly isolating problematic components.

 
LVL 1

Accepted Solution

by:
asarluhi earned 100 total points
ID: 6179415
OK - here's an example, including only the really salient parts of the configuration.  To address your question of how to manage the router, we'll use integrated routing and bridging (IRB) - which allows for the router to route packets that are specifically routable and bridges the rest.  In this instance, the address on the remote router (192.168.1.150) can be used to manage the device - but can be completely independent of any IP addressing used by your customer.  Check out Cisco's reference on IRB for more details:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/ibm_c/bcprt1/bcdtb.htm#xtocid1869460

central WAN router

(it is assumed that fe0 connects to your existing bridged backbone and that dlci 50 links you to your remote site - it is also assumed that this core router is also already managed out of band)

interface fastethernet0
no ip address
bridge-group 1

interface serial0
encapsulation frame-relay
interface serial0.1 point-to-point
bridge-group 1
frame-relay interface-dlci 50

bridge 1 protocol ieee

remote client router

(ethernet0 goes to local clients, dlci 40 links back to the central site and bvi 1 is used for in-band management)

interface ethernet0
no ip address
bridge-group 1

interface bvi 1
ip address 192.168.1.150 255.255.255.0

interface serial0
encapsulation frame-relay
interface serial0.1 point-to-point
bridge-group 1
frame-relay interface-dlci 40

bridge irb
bridge 1 route ip
bridge 1 protocol ieee


Now - with this in mind, I do agree with geoffryn's comments.  This isn't the optimal approach.  The performance isn't going to be great, and I'd pay close attention to the stability question.  If you need to support arbitrary IP addressing across a common backbone, check out MPLS-VPN.  I'd be happy to provide pointers if needed.

Good luck-
0
 
LVL 7

Author Comment

by:jjeff1
ID: 6179462
Please don't lock the question. I want to get feedback from everyone.
0
 
LVL 7

Author Comment

by:jjeff1
ID: 6288050
I am doing basically what asarluhi wrote. I made by serial interfaces and threw them, along with my ethernet interface into a bridge group.

Unfortunatly, the telco messed up the DLCIs, so I was unable to get anything to work.
0
 
LVL 7

Author Comment

by:jjeff1
ID: 6489003
Unfortunatly, I can't make this work at all.

I have been trying to use IRB with no luck.

As soon as I put the serial sub interface into a bridge group, all the PVC info dissappears from a show frame-relay pvc

0
 
LVL 7

Author Comment

by:jjeff1
ID: 6489053
Here is what I have on my core router:
!
interface ATM1/0.26 multipoint
 atm pvc 36 0 128 aal5snap
 bridge-group 26                    
!
interface Serial4/6
 no ip address
 encapsulation frame-relay IETF
 frame-relay lmi-type ansi
!
interface Serial4/6.1 point-to-point
 frame-relay interface-dlci 30
 bridge-group 26
!
interface Serial4/6.2 point-to-point
 frame-relay interface-dlci 31
 bridge-group 26
!
interface BVI26
 description gbar
 no ip address
!                  
bridge 26 protocol ieee
 bridge 26 route ip      


And on the edge :

Interface serial0
  no ip address
  encap frame-relay ietf
  frame-relay lmi-type ansi

interface serial0.1 point-to-point
  frame-relay interface dlci 16
  bridge group 1

bridge crb
bridge 1 protocol ieee

int ethernet0
no ip address
bridge-group 1

The edge router is running IOS 10.0 and does not have enough flash or RAM to upgrade.

I will see how this goes. I have had problems in the past, but this looks like it should all work.

Jeff
0
 
LVL 7

Author Comment

by:jjeff1
ID: 6715717
This is more or less what I ended up doing. I found that one of my problems was with the old code on one of my edge routers. The BVI simply did not work on the router, once I upgraded from 10 to 11 code, all was well.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Suggested Solutions

Creating an OSPF network that automatically (dynamically) reroutes network traffic over other connections to prevent network downtime.
Shadow IT is coming out of the shadows as more businesses are choosing cloud-based applications. It is now a multi-cloud world for most organizations. Simultaneously, most businesses have yet to consolidate with one cloud provider or define an offic…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

707 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now