Question:
we have here
R1, R2 Cisco 3560 Price and R3 that are in ospf 1 area 0.
we have ebgp
session from R1 to BGP1 and R2 to BGP2.
we have default
route in R1 and R2 pointing to FW (172.17.1.4) that are propagated with
default-info originate in OSPF and BGP too.
behind the
firewall there is a subnet 10.166.245.0/24 and there is a static route:
10.166.245.0 255.255.255.0 172.17.1.4 tag 1000
typically the
config from R1 or R2 is:
!
router ospf 1
log-adjacency-changes
redistribute
connected subnets route-map CONNECTED-2-OSPF
redistribute
static subnets route-map STATIC-2-OSPF
redistribute
bgp 65000 subnets route-map BGP-2-OSPF
passive-interface
default
no
passive-interface FastEthernet0/0
network 2.2.2 .0
0.0.0.255 area 0
!
router bgp
65000
no
synchronization
bgp
log-neighbor-changes
network 0.0.0 .0
redistribute
ospf 1 route-map OSPF-2-BGP
neighbor 2.2.2 .2
remote-as 65000
neighbor 2.2.2 .2
soft-reconfiguration inbound
neighbor 10.10.10 .1
remote-as 7000
neighbor 10.10.10 .1
soft-reconfiguration inbound
default-information
originate
no auto-summary
!
ip route 0.0.0 .0
0.0.0.0 172.17.1.4
ip route
10.166.245.0 255.255.255.0 172.17.1.4 tag 1000
!
!
route-map
STATIC-2-OSPF permit 10
match tag 1000
!
route-map
CONNECTED-2-OSPF permit 10
match interface
Vlan4
!
route-map
BGP-2-OSPF permit 10
set tag 50
!
route-map
OSPF-2-BGP deny 10
match tag 50
!
route-map
OSPF-2-BGP permit 20
match
route-type internal external
!
!
!
everybody knows
that by default only internal ospf routes are redistributed into bgp, but here
i wanted to redistribute the external ones too with route-map.
but no success.
in the bgp table of R1 and R2, there is 10.166.245.0/24 route !!!
i have a doubt:
does only the ospf routes that are in the routing table who can be
redistributed OR the routes in the OSPF database?
how can i
redistribute this static "10.166.245.0 255.255.255.0 172.17.1.4 tag
1000" into OSPF and then automatically to BGP ?
The deal is:
no
redistribution of static routes directly to BGP
no
"network 10.166.245.0 mask 255.255.255.0" command under bgp.
not change the
admin distance of static routes greater thant 110.
Answer:
generally, you
would need
router bgp
65000
redistribute
ospf 1 match internal external 1
external 2 route-map OSPF-2-BGP
command used to
redistribute both internal and external OSPF routes to BGP.
See
http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a00800943c5.shtml#redistributionofospfinternalandexternalroutesintobgp
for details.
But as you
describe, in your case the prefix is configured as a static one on your router.
So no matter if
redistributed to OSPF or not, it is still treated as static by your router.
If you want to
redistribute it to BGP, you need to redistribute static routes (with a
route-map permitting only this single prefix, if necessary).
I think there
is a good reason for this IOS behavior -
otherwise routing and redistribution loops could Cisco Catalyst 3560 be created easily.
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