Advertise a specific subnet to a BGP neighbour out of an aggregate

Dear all,
I just wanted to know what your thoughts are on the following issue that I have. I have an internal Router that receives various subnets of the 10.0.0.0/8 from internal core routers via an IGP. I have an IPBGP peering with a WAN router which has a static route 10.0.0.0/8 pointing back.
I need to advertise a specific subnet say 10.64.0.0/10. from the internal router to the WAN router who will then advertise to an EBGP peer.
However, when I do this I lose connectivity to the WAN router because it seems it ignores the 10.0.0.0/8 in favor of 10.64.0.0/10 because it is more specific.
I have added 10.0.0.0/10, 10.64.0.0/10 & 10.128.0.0/10 as static routes to the WAN router and I no longer lose connectivity. Any ideas of a better
solution ?

Yes but the original problem was that without the additional subnets you had static entries for you lost connectivity.
And you said it was because 10.64.0.0/10 was more specific.
But that is irrelevant because a static route will always be in the routing table unless you are modifying the AD.
Which means regardless of whether you are advertising a more specific subnet with BGP it makes no difference from the WAN routers perspective unless the subnet you are advertising via BGP is using a different next hop IP.
What is the next hop IP for the 10.0.0.0/8 static route on the WAN router ?
And what is the next hop IP for the 10.64.0.0/10 BGP route on the WAN router ?
Note not the static route you added but the BGP route.
Jon

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This is what i think would work.
Two assuptions i'm making -
1) R1 and R2 have full routes in terms of the remote branch subnets which from what we have talked about seems to be the case.
2) R1 will advertise the specific subnets it is primary for (see below) to R3 which then advertises them to R2 and R2 will do the same for it's primary subnets.
R1 is primary for 32 - 63 summary address 192.168.32.0 255.255.224.0
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is there a method for create a specific announce only for one neighbor on BGP session ? A possible solution can be filter in / out for neighbors but if is possible I won't avoid modifications on actual neighbors' configuration.
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Dear all:
In reference at the commands:
- sh bgp neighbor A.B.C.D
- sh bgp neighbor A.B.C.D received routes
- sh bgp neighbor A.B.C.D advertised-routes
For example:
ROUTER#sh bgp neighbor A.B.C.D
Policy for incoming advertisements is PEERING-IN
Policy for outgoing advertisements is PEERING-OUT
1 accepted prefixes, 0 are bestpaths
Cumulative no. of prefixes denied: 8974070.
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By ORF policy: 0, By policy: 8974070
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In output this command we have # Prefixes:
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advertised 77, suppressed 0, withdrawn 2 (after policy)
8974070 prefix are deny
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Processed 503233 prefixes, 503233 paths
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Processed 73 prefixes, 73 paths
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Not really because OSPF does not advertise routes it sends LSAs to it's peers.
So you need to look at the OSPF database ie. -
"sh ip ospf database"
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In terms of all the LSAs the router has received it will show all of those but it will also show you LSAs that were generated by the router itself although the advertising router IP will point to that being the case.
In terms of all the LSAs the router advertises again it depends on the area and how that has been configured.
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Advertise a specific subnet to a BGP neighbour out of an aggregate

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