06-27-2012 06:54 AM - edited 03-04-2019 04:48 PM
Hello
How do I control sending/receiving of routes on MPLS connection from HQ to Branch
Allow Branch to receive 192.168.1.0/24 & 192.168.2.0/24 routes only from HQ
Allow HQ to recieve 192.168.100.0/24 from branch only
Solved! Go to Solution.
06-27-2012 11:34 AM
Hello Vishal,
you just need network commands under router bgp process to advertise the IP subnets, if there are no other routers involved it is enough SP signalling plane will do all the job for you.
This is because network in BGP works differently that in IGP it looks for the IP prefix in the IP routing table and it can install and advertise a route learned by IGP.
You need redistribution of BGP into OSPF to propagate the routes learned in BGP
HQ CE
router bgp
network 192.168.1.0
network 192.168.2.0
neighbor HQ-PE-ip-address remote-as SP-AS
access-list 22 permit 192.168.100.0
route-map BGP-to-OSPF permit 10
match ip address 24
router ospf 1
redistribute bgp
Branch CE
router bgp
network 192.168.100.0
neighbor BR-PE-ip-address remote-as SP-AS
access-list 24 permit 192.168.1.0
access-list 24 permit 192.168.2.0
route-map BGP-to-OSPF permit 10
match ip address 24
router ospf 1
redistribute bgp
note: all this works if there is no alternative path between the sites, under the hyphothesis the OSPF domains are not joined between the sites.
Hope to help
Giuseppe
06-27-2012 09:25 AM
Hi,
What kind of routing do you use between pe and ce?
Regards,
Sent from Cisco Technical Support iPad App
06-27-2012 10:16 AM
PE - to - CE its BGP
LAN its OSPF
06-27-2012 11:30 AM
the simplest thing will be using static route and then redistribute this route to the bgp.
perhaps you can post show run from the HQ and Branch1 CE router.
regards,
06-27-2012 11:34 AM
Hello Vishal,
you just need network commands under router bgp process to advertise the IP subnets, if there are no other routers involved it is enough SP signalling plane will do all the job for you.
This is because network in BGP works differently that in IGP it looks for the IP prefix in the IP routing table and it can install and advertise a route learned by IGP.
You need redistribution of BGP into OSPF to propagate the routes learned in BGP
HQ CE
router bgp
network 192.168.1.0
network 192.168.2.0
neighbor HQ-PE-ip-address remote-as SP-AS
access-list 22 permit 192.168.100.0
route-map BGP-to-OSPF permit 10
match ip address 24
router ospf 1
redistribute bgp
Branch CE
router bgp
network 192.168.100.0
neighbor BR-PE-ip-address remote-as SP-AS
access-list 24 permit 192.168.1.0
access-list 24 permit 192.168.2.0
route-map BGP-to-OSPF permit 10
match ip address 24
router ospf 1
redistribute bgp
note: all this works if there is no alternative path between the sites, under the hyphothesis the OSPF domains are not joined between the sites.
Hope to help
Giuseppe
06-27-2012 12:38 PM
Thanks Giuseppe
I tested your config and it works perfect.
<
In Branch CE
Router BGP 64500
network 192.168.100.0
I want HQ to receive subnet 192.168.100.0/24 except host 192.168.100.254.
can you tell how to get this working
thanks
Vishal
06-28-2012 12:41 AM
Hello Vishal,
>> I want HQ to receive subnet 192.168.100.0/24 except host 192.168.100.254.
This cannot be performed with routing, it requires the use of an ACL for example applied outbound on interface to PE router
BR-CE:
access-list 121 remark denying access to host
access-list 121 deny ip host 192.168.100.254 192.168.1.0 0.0.1.255 log
access-list 121 permit ip any any
interface type x/y
description interface to BR-PE
ip access-group 121 out
In this way HQ subnets cannot talk with the specific host
Hope to help
Giuseppe
06-28-2012 01:05 AM
hi Giuseppe,
i think the access list is better at the inside interface of HQ-CE (the lan interface). this way the traffic to specific host do not utilizing the network and finally get dropped.
regards,
06-28-2012 05:44 AM
Thanks Giuseppe
All worked perfectly well as u mentioned.
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