From: Connary, Julie Ann (jconnary@xxxxxxxxx)
Date: Fri Jan 05 2001 - 19:00:03 GMT-3
Hi All,
I fully realize that route-reflectors are a replacement for fully-meshed
IBGP. Hence my question why
R3 should get the route at all since it is not internally peered to
R5 and R1 is not setup to reflect to it - although it seems to be doing
just that.
Sorry - long day - I'm going home now. If anyone has any ideas why R1 would
reflect an internal
router to another internal peer that is not a route-reflector client ---------
Julie Ann
At 04:41 PM 1/5/2001 -0500, David C Prall wrote:
>I believe this is confusion between internal and external routes. Internal
>BGP routers must be fully meshed, they only advertise their local networks
>to other internal neighbors. External BGP routes will be advertised to other
>internal neighbors. The use of a route reflector allows internal routes to
>be advertised to other internal routers, thus relieving the need for a fully
>meshed topology.
>
>David C Prall dcp@dcptech.com http://dcp.dcptech.com
>----- Original Message -----
>From: "Connary, Julie Ann" <jconnary@cisco.com>
>To: <ccielab@groupstudy.com>
>Sent: Friday, January 05, 2001 4:23 PM
>Subject: route-reflector question
>
>
> > Hi All,
> >
> > I have a frame-relay hub and spoke network with the hub as the
> > route-reflector server and the spokes as clients.
> >
> >
> > R3---------------EBGP ---------R4
> > | 137.20.34.3 137.20.34.4
> > | 137.20.1.3
> > |
> > IBGP
> > |
> > |
> > | 137.20.1.1 137.20.1.5 137.20..129.5 137.20.129.7
> > R1-----------------ibgp ---------R5----------EBGP ------------R7
> >
> >
> > R1 is the frame-relay hub with R3 and R5 as spokes.
> > R7 is initiating a route - 160.0.0.0/4. R4 is also intiating a route -
> > 172.168.2.0
> > I had setup R1 to route-reflect to R5, but not to R3. So I had expected
> > that R5 would see the
> > route from R4, but R3 should not see the route from R7 - as R1 should not
> > reflect it - correct?
> >
> > On R3 I see the following:
> >
> > r3#show ip bgp
> > BGP table version is 33, local router ID is 137.20.31.65
> > Status codes: s suppressed, d damped, h history, * valid, > best, i -
>internal
> > Origin codes: i - IGP, e - EGP, ? - incomplete
> >
> > Network Next Hop Metric LocPrf Weight Path
> > *>i160.0.0.0/4 137.20.129.7 100 0 3 i
> > *> 172.168.2.0/24 137.20.34.4 0 0 1 ?
> >
> > r3#show ip bgp 160.0.0.0
> > BGP routing table entry for 160.0.0.0/4, version 33
> > Paths: (1 available, best #1)
> > 3, (aggregated by 3 170.10.10.1)
> > 137.20.129.7 (metric 84) from 137.20.1.1 (137.20.129.5)
> > Origin IGP, localpref 100, valid, internal, atomic-aggregate, best
> > Originator : 137.20.129.5, Cluster list: 137.20.11.33
> >
> > With a BGP setup of:
> >
> > !
> > router bgp 2
> > neighbor 137.20.1.1 remote-as 2
> > neighbor 137.20.34.4 remote-as 1
> >
> >
> > On R1 I see:
> >
> > r1#show ip bgp
> > BGP table version is 25, local router ID is 137.20.11.33
> > Status codes: s suppressed, d damped, h history, * valid, > best, i -
>internal
> > Origin codes: i - IGP, e - EGP, ? - incomplete
> >
> > Network Next Hop Metric LocPrf Weight Path
> > *>i160.0.0.0/4 137.20.129.7 100 0 3 i
> > *>i172.168.2.0/24 137.20.34.4 0 100 0 1 ?
> >
> > r1#show ip bgp 160.0.0.0
> > BGP routing table entry for 160.0.0.0/4, version 25
> > Paths: (1 available, best #1, advertised over IBGP)
> > 3, (aggregated by 3 170.10.10.1), (Received from a RR-client)
> > 137.20.129.7 (metric 84) from 137.20.1.5 (137.20.129.5)
> > Origin IGP, localpref 100, valid, internal, atomic-aggregate, best
> >
> > with a bgp setup of:
> >
> > router bgp 2
> > no synchronization
> > neighbor 137.20.1.3 remote-as 2
> > neighbor 137.20.1.5 remote-as 2
> > neighbor 137.20.1.5 route-reflector-client
> > neighbor 137.20.12.2 remote-as 2
> > neighbor 137.20.12.2 route-reflector-client
> >
> > (note that 137.20.1.3 is not a route-reflector-client.)
> >
> > On R5 I have:
> >
> > r5#show ip bgp
> > BGP table version is 3, local router ID is 137.20.129.5
> > Status codes: s suppressed, d damped, h history, * valid, > best, i -
>internal
> > Origin codes: i - IGP, e - EGP, ? - incomplete
> >
> > Network Next Hop Metric LocPrf Weight Path
> > *> 160.0.0.0/4 137.20.129.7 0 3 i
> > *>i172.168.2.0/24 137.20.34.4 0 100 0 1 ?
> > r5#show ip bgp 160.0.0.0
> > BGP routing table entry for 160.0.0.0/4, version 3
> > Paths: (1 available, best #1, advertised over IBGP)
> > 3, (aggregated by 3 170.10.10.1)
> > 137.20.129.7 from 137.20.129.7 (170.10.10.1)
> > Origin IGP, valid, external, atomic-aggregate, best
> >
> > with a setup of:
> >
> > router bgp 2
> > no synchronization
> > neighbor 137.20.1.1 remote-as 2
> > neighbor 137.20.129.7 remote-as 3
> > !
> >
> >
> >
> > any ideas why R3 sees this route? Is this correct?
> >
> > thanks,
> >
> > Julie Ann
> >
> >
> > ------------------------------------------------------------------------
> > Julie Ann Connary
> > | | Network Consulting Engineer
> > ||| ||| Federal Support Program
> > .|||||. .|||||. 13635 Dulles Technology Drive,
> > Herndon VA 20171
> > .:|||||||||:.:|||||||||:. Pager: 1-888-642-0551
> > c i s c o S y s t e m s Email: jconnary@cisco.com
> >
> > ------------------------------------------------------------------------
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