Service provider "StoryTellers" is intrigued by your performance so far, before they allow you to even look at their production MPLS backbone there is another lab they would like you to configure another lab. By using MPLS VPN's it's possible to send customer routes over the provider network. OSPF will be configured in the service provider domain (Router SP1, SP2 and SP3), the customer will be using EIGRP.
Goal:
Configure all IP addresses as specified in the topology picture.
Configure a loopback0 interface on each router: HQ: 1.1.1.1 /25 SP1: 2.2.2.2 /25 SP2: 3.3.3.3 /25 SP3: 4.4.4.4 /25 BRANCH: 5.5.5.5 /25
Configure OSPF Area 0 at the provider side (Router SP1, SP2 and SP3).
Advertise the loopback interfaces as well in OSPF.
Ensure you have full reachability in the OSPF domain.
Configure MPLS on all physical interfaces in the service provider domain, do not configure MPLS on physical interfaces pointing towards the customer.
Force MPLS to use the loopback interface as router-id.
Configure VRF "customer" on SP1 and SP3 as following: RD 100:1 Route-target both 1:100
On router SP1 and SP3 add the interfaces pointing towards the customer to the VRF you just created.
Ensure you can ping from within the VRF, try this as following on SP1: ping vrf customer 192.168.12.1
Configure EIGRP AS 100 on router HQ and Branch. Advertise the loopbacks as well.
Configure EIGRP on router SP1 and SP3 for the correct VRF "customer".
Ensure you have established a EIGRP neighbor relationship between Router HQ and SP1, and between SP3 and Branch.
See if you have learned routes by using "show ip route vrf customer".
Configure BGP AS 1 between Router SP1 and SP3, make sure updates are sources from the loopback interface.
Configure the correct BGP address families and make sure communities are sent between neighbors.
Redistribute EIGRP into BGP, use the correct address-family for the VRF "customer".
Redistribute the information from BGP back into EIGRP, use the following metrics: bandwidth: 64kbps delay: 1000 reliability: 255 load: 1 MTU: 1500
Ensure you have full connectivity between router HQ and Branch. You should see each other's EIGRP routes that have been carried over the service provider's MPLS backbone.
Optional: Replace the Customer's EIGRP with OSPF / RIP or BGP and achieve the same result.
IOS:
c3640-jk9s-mz.124-16.bin
Topology:
Video Solution:
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Do I understand correctly that 3.3.3.3/30 is the broadcast address for subnet 3.3.3.0/30?
Also, is 4.4.4.4/30 the subnet address for 4.4.4.4/30?
If so, how can these be assigned to interfaces? I keep getting "bad mask" errors when I try.
For now, I will just use /29, and see how that goes...
Only i can download the topology.But i need the configuration of the each router.Can anyone share the configuration for the above topology as i am in need.
Thanks in advance
Mr.KD
About the loopbacks, I messed up on that one...you are correct Doug. 3.3.3.3/30 is a broadcast address. I changed the loopbacks all to /25's, it doesn't matter much what kind of address you have on the loopbacks.
Frank, the download link is at the bottom of every article...below the topology picture.
Mr.Kd, what kind of config would you like to see here? a basic config which has the IP addresses or a final configuration with the working solution? Right now I don't supply any configs but I think I will in the future...it's very time consuming to create 'startup' configs and 'final' configs as well.
Hi Rene
I am new to MPLS and so i just want to know how to configure MPLS for the above topology.So i request for the configuration so that i will get some ideas and i can create my own topologies.
I did this one of top of my head, but it should be pretty accurate. I didn't include the OSPF part for the backbone, just the MPLS.
// SP1, SP2 and SP3 should have MPLS enabled on the interfaces towards each other...NOT to the customer!
router (config)# interface f0/0
router (config)# mpls ip
// force MPLS to use the loopback's router ID:
router (config) mpls ldp router-id loopback0
// now the VRF part. A VRF is like a 'virtual routing table', kinda like a VLAN but now for L3. Let's create the VRF first, you need to do this on SP1 and SP3:
router (config)# ip vrf CUSTOMER
Router(config-vrf)#
// now we setup the RD (route distinguisher) which is needed to make the customers prefixes unique in our MPLS VPN setup.
Router(config-vrf)# rd 100:1
// Next step is to configure the correct route-target. The RT is what 'creates' the VPN:
// Now we need to add the interfaces pointing towards the customer into the correct VRF, do this on SP1 and SP3 (example is for SP1):
Router(config)# interface f1/0
Router(config-if)# ip vrf forwarding CUSTOMER
// you need to reassign the IP address...but it will tell you.
Try to ping the customer router from the VRF: (example SP1)
// ping vrf CUSTOMER 192.168.45.5
// Now you need to enable routing between the PE routers and the customer router, and we are using EIGRP. The difference is you need to specify the VRF when configuring EIGRP, this is how you do it:
Router(config)# Router EIGRP 100
Router(config-router)#address-family ipv4 vrf CUSTOMER
// then add all the network statements there...
// At this moment, you should have a working EIGRP between the SP and the Customer.
// You should have MPLS running on the SP routers.
// The next step is to get BGP going between SP1 and SP3, we'll use multi-protocol BGP (MP-BGP) to get those prefixes to the other side. You don't need to configure BGP on SP2!
// example is for SP1
// we need to send community information:
Router(config-router)# address-family vpnv4
Router(config-router-af)# neighbor 4.4.4.4 activate
Router(config-router-af)# neighbor 4.4.4.4 send-community extended
// Now we want to get those prefixes to the other side, we need to redistribute from EIGRP to BGP and the other way around.
Glad you like it With the same topology you can try to have RIP, OSPF or BGP exchanged for the customer...it's kinda the same but a little bit different.
So if I understand correctly...you want to do this
SP1 SWITCH vlan 10+20
Connect HQ-A in Vlan10
Connect Branch-B in vlan 20
SP3 SWITCH vlan 10+20
Connect HQ-B in vlan 20
Connect Branch-A in vlan 10
If you would build a trunk from the switch to the router and create sub-interfaces on the SP routers...that would work, but why would you want to do this? This isn't something you would see or do in a real life situation..
Keep in mind a switch is a layer2 vlan, and a VRF is kinda like a "layer 3 vlan"
From the start of the posts I noted a one side of a coin and then the other. I see that some issues were addressed with the "config" and then a video added. Hats off to Rene; I've been looking at topologies in manuals, books, PDFs and building from them and having to look up a log of stuff along the way. I have found many errors from Authors and I have learned a lot more by having to look things up to make it work. I lost several hours worth of study time from today this evening, but I then went the extra mile to ensure that I save my topologies correctly, as I will work on something and then switch over for a while due to something I read. It can be good to have config's to compare against but I am really glad that when I download a lab I have to build out from the image.
Rene, if you decide to add completed configs, can you still have it so we have to... well there is always write erase... wr reload .
I've been kinda busy with work so I didn't have time for MPLS labs...if you have some topologies and tasks please send them over, i'll wrap them into a nice article for the site!
Speaking for myself... I would welcome more labs. The more the better. In response to Rene's post regarding the start up config, I have several in as text files that I use for a always needed basics... if your using DHCP Pool & exclusions, router - EIGRP/OSPF/ect {AS#'s} XXXX. Line COn 0 settings... ect.
Thanks again for the site,
JCB
aneesh2010-12-12 20:04:33
its so helpul in our studies.... more labs wil b helpful.....
Ok so I am new to this and would like to know how to get the IOS images to work. I have found a bunch of IOS .bin files and tried loading them into the GSN3 program but when I try to load the topology from the file above it tells me that my IOS files are in bad paremeter. Any ideas and where did you guys get yours??
DT- really the only solution if you're unable to get the same IOS version is to build the lab from scratch. I do the same thing with my labs. Doesn't take too much longer....
imran.palmeera2011-07-27 10:33:48
To configure IBGP between SP1 & SP3 why didnt you use inside the address family ?
it's interesting to note when configuring the bgp vpnv4 send-community parameter that can appear an error message regarding the peering between bgp neighbors along the loopback interface. As i experienced the problem during the configuration i received a message like :"G;P-4-VPNV4NH_MASK : Nexthop 4.4.4.4 may not be reachable from neigbor 2.2.2.2 - not /32 mask". After wonder around some possible causes of the problem i remembered that changing the ospf network type we can influence the appearance of the mask of loopback interface. As we were running ospf i changed that under lo0 and everything worked like charme.So bgp expect always an host mask to form neighborship over vpnv4 address-family and if we pass it a network mask the neighborship will fail anyway.
Quick question, on the routers where you saw this error you already had MPLS LDP enabled on the interface? If so...what happens when you disable MPLS and keep the /24 on the interface without changing the OSPF network type?
Hi Rene,
yes the mpls part was completed, and the behaviour is the same without mpls enabled. I've paid more attention this time to the error and i noted that the redistribution of eigrp into bgp trigger the notification. It's like if eigrp routes before to reach bgp are influenced by ospf net-type. But i honestly can't figured out why because until have no redistribution seems everything fine...what you think about it?
I m also not able to see the topology file. Is it a zip. file or sth else? i have downloaded topologies for some other labs like VRF-Lite but that one. Could you please have a look?
Even if im already registered i only see this:
You need to register to be able to download the GNS3 Topology File. (Registration is Free!)
Hi, Firstly I'd like to thank you for this lab, the resources and the videos, they've been very helpful. I've been working through the lab solution on your videos and I've gotten right to the end of Part 3. However the final 2 pings don't work for me. Even when I download the Final Configs from here, the last 2 pings don't work for me. Does anyone know why? Or what I could do to check?
I have been following the commands in the videos one by one and everything looks identical to your results e.g. if I run the "show ip route vrf CUSTOMER" command I get the same result as in the video. As I said it's just the last two pings to ensure that the HQ and the Branch have end to end connectivity that is failing.
Apologies, I just loaded up the topology and the configs again, and the ping is working this time. It's a bit of a mystery to be honest as I haven't done anything differently from last time. At least it's working now anyway, so thanks again!
There are a number of things to check when you are troubleshooting MPLS:
1. Check the BGP adjacency between the PE routers.
2. Check the VRF routing table and see if you can ping from the PE by using the VRF table (ping vrf
3. Check the BGP and IGP (OSPF, RIP, EIGRP) table/database to see if your redistribution is ok.
4. You can also check if there's a label by using the "show mpls ldp bindings" command.
It depends on the ISP solution, it's possible that you will get an Ethernet connection from the ISP to the customer.
For some of the labs I chose FastEthernet because you won't have any layer1 or layer2 issues. If the lab is about MPLS I don't want people to start struggling with layer1 or layer2 frame-relay issues or anything else so they only have to focus on MPLS
Question: Why use two Routing Protocols Within the Service Provider. Is this a realistic scenario ?? would the service Provider simple use a BGP route between them and the Customer?? Just curious. .
This is a good example of a real MPLS network. This is what happens:
- Within the MPLS "core" we will run an IGP like OSPF to advertise all the loopback interfaces.
- All the PE routers will run IBGP to exchange routing information.
- Beween the PE and CE (customer) routers you can use whatever routing protocol you like...OSPF, EIGRP but also BGP. It depends on the customer requirements.
Keep in mind that whatever the customer advertises to you will be stored in a VRF (virtual routing table).
I notice that mostly all the labs use Fast-Ethernet or Ethernet for making connection would WAN links be a more realistic representation of ISP connections over distance to the Customer or is their a draw back to this approach ??
I use the Ethernet / FastEthernet links to keep things simple. In this lab I'm just focusing on the MPLS part and it would be bad if you also have to think about layer 2 issues with PPP, HDLC or Frame-Relay
I would like to thank you for the free video lab's. I took a look at all the labs. I wached the basic mpls vpn video and I appreciated so much that I tried to implment it in my own and it took me so much time to be able to do it.
I have only a small feedback, namely when implementing the video's. My remak is that you type very fast and ypu give very little explanation fo the command you are enering. I am CCNA and have a baisc MPLS and routing protocols and theri implementation.
So, please try to have more time during you explanation especially for the beginners and your video's will be very valuable and competitive. May thanks for help.
Thanks for your kind words and comments. In my future videos I'll make sure to type a bit slower and take my time to explain things. I do "assume" however that people have read/learned a bit about the background theory of the protocols because it's hard to explain theory + the implementation at the same time I hope it's helpful to you and i'll do my best in the future!
excellent LAB loved watching it..... Appreciation and thank you for the effort.... One thing I would like to notify here is I am not able to download the zip files attached to LAB can you please help....