RE: EIGRP Backdoor

Thanks Brian for the explanation , Can you give me an IOS image from the older ones (the name) so that I can test the SOO more clearly

BR,

> From: bmcgahan_at_ine.com
> To: eng_mssk_at_hotmail.com
> CC: ccielab_at_groupstudy.com
> Date: Wed, 27 Nov 2013 10:27:32 -0600
> Subject: Re: EIGRP Backdoor
>
> No you don't need SoO because of the EIGRP metric encoding. SoO was only needed in older versions.
>
> Brian McGahan, 4 x CCIE #8593 (R&S/SP/SC/DC), CCDE #2013::13
> bmcgahan_at_INE.com<mailto:bmcgahan_at_INE.com>
>
> Internetwork Expert, Inc.
> http://www.INE.com<http://www.ine.com/>
>
> On Nov 27, 2013, at 8:27 AM, "Mohammad Khalil" <eng_mssk_at_hotmail.com<mailto:eng_mssk_at_hotmail.com>> wrote:
>
> Thanks Brian for the reply
> What is not clear for me is
> When I configure redistribution on both PE routers , I get the below
>
> R3#sh ip route eigrp
> Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
> D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
> N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
> E1 - OSPF external type 1, E2 - OSPF external type 2
> i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
> ia - IS-IS inter area, * - candidate default, U - per-user static route
> o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
> + - replicated route, % - next hop override
>
> Gateway of last resort is not set
>
> 4.0.0.0/32 is subnetted, 1 subnets
> D 4.4.4.4 [90/158720] via 192.1.13.1, 00:01:02, FastEthernet1/0
> D 192.1.24.0/24 [90/30720] via 192.1.13.1, 00:01:02, FastEthernet1/0
>
> R3#ping 4.4.4.4 source lo0
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:
> Packet sent with a source address of 3.3.3.3
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 12/25/36 ms
>
> R3#traceroute 4.4.4.4 source lo0 numeric
> Type escape sequence to abort.
> Tracing the route to 4.4.4.4
> VRF info: (vrf in name/id, vrf out name/id)
> 1 192.1.13.1 24 msec 8 msec 8 msec
> 2 192.1.24.2 [MPLS: Label 18 Exp 0] 24 msec 16 msec 12 msec
> 3 192.1.24.4 16 msec * 16 msec
>
> R4#sh ip route eigrp
> Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
> D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
> N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
> E1 - OSPF external type 1, E2 - OSPF external type 2
> i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
> ia - IS-IS inter area, * - candidate default, U - per-user static route
> o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
> + - replicated route, % - next hop override
>
> Gateway of last resort is not set
>
> 3.0.0.0/32 is subnetted, 1 subnets
> D 3.3.3.3 [90/158720] via 192.1.24.2, 00:01:24, FastEthernet1/0
> D 192.1.13.0/24 [90/30720] via 192.1.24.2, 00:01:24, FastEthernet1/0
>
> R4#ping 3.3.3.3 source lo0
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
> Packet sent with a source address of 4.4.4.4
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 16/24/32 ms
>
> R4#traceroute 3.3.3.3 source lo0 numeric
> Type escape sequence to abort.
> Tracing the route to 3.3.3.3
> VRF info: (vrf in name/id, vrf out name/id)
> 1 192.1.24.2 12 msec 8 msec 4 msec
> 2 192.1.13.1 [MPLS: Label 17 Exp 0] 12 msec 16 msec 20 msec
> 3 192.1.13.3 24 msec * 16 msec
>
> I have no loops taking place at the time , so do I really need to configure soo ?
>
> And If I configured SOO ( as you can see above , am preferring the mpls backbone right now before applying soo)
>
> R1,R2
> route-map SOO_MAP permit 10
> set extcommunity soo 100:1
> int f1/1
> ip vrf sitemap SOO_MAP
>
> R3#sh ip route eigrp
>
> 4.0.0.0/32 is subnetted, 1 subnets
> D 4.4.4.4 [90/2297856] via 192.1.34.4, 00:00:43, Serial2/0
> D 192.1.24.0/24 [90/2172416] via 192.1.34.4, 00:00:43, Serial2/0
>
> R4#sh ip route eigrp
>
> 3.0.0.0/32 is subnetted, 1 subnets
> D 3.3.3.3 [90/2297856] via 192.1.34.3, 00:01:37, Serial2/0
> D 192.1.13.0/24 [90/2172416] via 192.1.34.3, 00:00:40, Serial2/0
>
> So , the route is learned now via the backdoor link , and I want to keep learning it from the MPLS backbone
>
> > From: bmcgahan_at_ine.com<mailto:bmcgahan_at_ine.com>
> > To: eng_mssk_at_hotmail.com<mailto:eng_mssk_at_hotmail.com>; ccielab_at_groupstudy.com<mailto:ccielab_at_groupstudy.com>
> > Date: Tue, 26 Nov 2013 17:10:49 -0600
> > Subject: RE: EIGRP Backdoor
> >
> > If you want to learn the routes in the backdoor link then increase the delay
> > on the CE link facing towards the PE. Changing the seed metric for EIGRP to
> > VPNv4 BGP redistribution isn't going to affect anything, since the metrics
> > from the EIGRP database are automatically copied in and overwrite whatever
> > seed metric you set.
> >
> > The only time the seed metric matters is if the individual EIGRP vector
> > metrics didn't get encoded in the VPNv4 update. This could happen because you
> > have EIGRP on one side but a different protocol on the other side, if you do
> > some sort of Inter-AS routing exchange that strips the extended communities
> > that encoded the EIGRP vector metrics (e.g. Inter-AS Option A with IPv4
> > Unicast EBGP as the PE to PE routing protocol) , or if you're running an older
> > IOS version that didn't support the encoding to begin with.
> >
> > If you "show bgp vpnv4 unicast all x.y.w.z/len" on the PE router doing the
> > redistribution you can see in the VPNv4 update what metrics have been set.
> >
> > Brian McGahan, 4 x CCIE #8593 (R&S/SP/SC/DC), CCDE #2013::13
> > bmcgahan_at_INE.com<mailto:bmcgahan_at_INE.com><mailto:bmcgahan_at_INE.com>
> >
> > Internetwork Expert, Inc.
> > http://www.INE.com<http://www.ine.com/>
> >
> > From: Mohammad Khalil [mailto:eng_mssk_at_hotmail.com]
> > Sent: Tuesday, November 26, 2013 12:56 PM
> > To: Brian McGahan; ccielab_at_groupstudy.com<mailto:ccielab_at_groupstudy.com>
> > Subject: RE: EIGRP Backdoor
> >
> > OK if i wanted the routes to be learned through the backbone in this case what
> > should i do? Increase the delay on the backdoor or should i change the eigrp
> > seed metric when redistribution?
> > Thanks
> >
> > > From: bmcgahan_at_ine.com<mailto:bmcgahan_at_ine.com><mailto:bmcgahan_at_ine.com>
> > > To: eng_mssk_at_hotmail.com<mailto:eng_mssk_at_hotmail.com><mailto:eng_mssk_at_hotmail.com>;
> > ccielab_at_groupstudy.com<mailto:ccielab_at_groupstudy.com><mailto:ccielab_at_groupstudy.com>
> > > Date: Tue, 26 Nov 2013 10:04:38 -0600
> > > Subject: RE: EIGRP Backdoor
> > >
> > > That's normal. Your metric of 1 1 1 1 1 doesn't apply because the EIGRP
> > metric is automatically encoded into the VPNv4 BGP update, and then copied
> > back into EIGRP when you redistribute it back on the other side. The SoO is
> > normal too. By using the same value on the PE-CE links you're basically
> > filtering those routes out.
> > >
> > > Brian McGahan, 4 x CCIE #8593 (R&S/SP/SC/DC), CCDE #2013::13
> > > bmcgahan_at_INE.com<mailto:bmcgahan_at_INE.com><mailto:bmcgahan_at_INE.com>
> > >
> > > Internetwork Expert, Inc.
> > > http://www.INE.com
> > >
> > >
> > > -----Original Message-----
> > > From: nobody_at_groupstudy.com<mailto:nobody_at_groupstudy.com><mailto:nobody_at_groupstudy.com>
> > [mailto:nobody_at_groupstudy.com] On Behalf Of Mohammad Khalil
> > > Sent: Tuesday, November 26, 2013 5:02 AM
> > > To: ccielab_at_groupstudy.com<mailto:ccielab_at_groupstudy.com><mailto:ccielab_at_groupstudy.com>
> > > Subject: EIGRP Backdoor
> > >
> > > Hi All
> > > I have the below topology
> > > R1 -- R2
> > > | |
> > > R3 -- R4
> > >
> > > All connections are FE except for the backdoor which is serial I have
> > configured EIGRP as the PE-CE routing protocol between PE and CE (my PEs are
> > R1 and R2) When I redistributed BGP into EIGRP I used a metric of 1 1 1 1 1 I
> > see routes of My CEs through the MPLS backbone When I configured soo through
> > the route-map and applied the ip vrf sitemap on the PE-CE interface , I see
> > the routes now through the backdoor link , is that what suppose to happen or
> > am missing something ?
> > >
> > > Thanks
> > >
> > >
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Received on Wed Nov 27 2013 - 22:54:55 ART