This article explains how to configure eBGP between Versa FlexVNF CPE and remote PE router.
Please refer to this topology diagram for explanation in this article.
Scenario
We have to configure an EBGP session between Versa Flex VNF and a remote PE router. Remote PE router is a part of an autonomous system 64514 going to establish the EBGP session with Versa FlexVNF administered under Local AS 64515.
Once EBGP peering comes alive we will start receiving remote BGP route (120.168.10.10) in Flex VNF.
Configuration
- Login to Versa Director GUI to configure the Go to Appliance > Configuration> Networking>Virtual Routers
- Click on the WAN routing-instance (in our example mpls2-Transport-VR)
- Select BGP and click on + tab to configure BGP instance.
- Configure BGP Instance ID, Local AS and Router ID as specified and then click on Peer Group
- Configure BGP type(IBGP or EBGP), Peer AS, Local Address. Peer AS number should be the AS number of the remote PE router and local address field should be configured with the address bind to local interface present in the WAN routing-instance (mpls2-Transport-VR).
This local address will be used as a source address to create underlying TCP session.
- Click on Neighbors tab
- Configure BGP Neighbor address:
BGP Neighbor address field should be populated with an IP address configured at the remote router interface in order to establish the BGP session. Versa Flex will use this as a destination address for establishing underlying TCP connection to remote PE router.
This completes the configuration on Versa FlexVNF CPE.
Cli Configuration
admin@cpe1-cli> show configuration routing-instances mpls2-Transport-VR | display set
set routing-instances mpls2-Transport-VR instance-type virtual-router
set routing-instances mpls2-Transport-VR networks [ mpls2 ]
set routing-instances mpls2-Transport-VR routing-options static route 0.0.0.0/0 85.85.85.1 none tag 0
set routing-instances mpls2-Transport-VR protocols bgp 4000 router-id 85.85.85.2
set routing-instances mpls2-Transport-VR protocols bgp 4000 local-as as-number 64515
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE type external
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE family inet unicast
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE family inet unicast prefix-limit-control action drop
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE local-address 85.85.85.2
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE peer-as 64514
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE neighbor 85.85.85.1 prefix-limit
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE neighbor 85.85.85.1 prefix-limit threshold 75
set routing-instances mpls2-Transport-VR protocols bgp 4000 group To-PE neighbor 85.85.85.1 prefix-limit restart-interval 90
Validation:
admin@cpe1-cli> show bgp neighbor brief
routing-instance: mpls2-Transport-VR
Neighbor V MsgRcvd MsgSent Uptime State/PfxRcd PfxSent AS
85.85.85.1 4 27 25 00:10:10 2 0 64514
admin@cpe1-cli> show route routing-instance mpls2-Transport-VR
Routes for Routing instance : mpls2-Transport-VR AFI: ipv4
Codes: E1 - OSPF external type 1, E2 - OSPF external type 2
IA - inter area, iA - intra area,
L1 - IS-IS level-1, L2 - IS-IS level-2
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
RTI - Learnt from another routing-instance
+ - Active Route
Prot Type Dest Address/Mask Next-hop Age Interface name
---- ---- ----------------- -------- --- --------------
static N/A +0.0.0.0/0 85.85.85.1 00:22:59 vni-0/4.0
conn N/A +85.85.85.0/24 0.0.0.0 00:22:59 vni-0/4.0
local N/A +85.85.85.2/32 0.0.0.0 00:22:59 directly connected
BGP N/A +120.168.10.10/32 85.85.85.1 00:00:19 vni-0/4.0 <<<<<<<<<<<Remote Ebgp route received from PE router
Routes for Routing instance : mpls2-Transport-VR AFI: ipv6