I have configured BGP aggregate addresses for RFC1918 address space on our WAN routers towards our core switches to reduce the routing tables sizes on our LAN devices. I have configured an unsuppress-map on our WAN peering to allow our local networks which are part of the RFC1918 address space to be advertised out. I also have a route-map for prepending so we can load share traffic over both our WAN links but since applying the unsuppress-map the prepending in the route-map is no longer applied:
router bgp 65100
bgp router-id 192.168.0.1
bgp log-neighbor-changes
network 192.168.0.1 mask 255.255.255.255
aggregate-address 192.168.0.0 255.255.0.0 summary-only
aggregate-address 172.16.0.0 255.240.0.0 summary-only
aggregate-address 10.0.0.0 255.0.0.0 summary-only
timers bgp 5 15
neighbor 10.255.0.1 remote-as 65160
neighbor 10.255.0.1 description BGP IP/VPN
neighbor 10.255.0.1 route-map RM-BGP-OUT out
neighbor 10.255.0.1 unsuppress-map RM-BGP-LEAK
neighbor 10.255.0.6 remote-as 65100
neighbor 10.255.0.6 route-map RM-LAN-IN in
route-map RM-BGP-OUT deny 10
match ip address prefix-list PL-RFC1918
route-map RM-BGP-OUT permit 20
match ip address prefix-list PL-HSRP-MASTER
route-map RM-BGP-OUT permit 30
set as-path prepend 65100
route-map RM-BGP-LEAK permit 10
match as-path 1
ip as-path access-list 1 permit ^$
ip prefix-list PL-RFC1918 seq 5 permit 10.0.0.0/8
ip prefix-list PL-RFC1918 seq 10 permit 172.16.0.0/12
ip prefix-list PL-RFC1918 seq 15 permit 192.168.0.0/16
ip prefix-list PL-HSRP-MASTER seq 5 permit 10.1.0.0/24
ip prefix-list PL-HSRP-MASTER seq 10 permit 10.1.1.0/24
