Asymmetric EVPN IRB
Example model & SONiC version:
- Aurora 610, Aurora 615, Aurora 715
- Netberg SONiC: SONiC.202111-nba610-support, SONiC.master.0-20220721, SONiC.202012-nb-inno3
Asymmetric IRB feature list
- Ingress VTEP needs MAC DA of the destination system.
- Egress VTEP only bridges after decapsulation.
- No L3 VNI concept, however VRFs can be created for each tenant. Can be in default VRF as well.
- Asymmetric IRB can work with centralized routing.
Mac/route table usage
- MAC Table – all end hosts
- Neighbor Table – all end hosts
- Route Table – all end hosts
- VNIs – all VNIs in fabric
Scenarios for using Asymmetric IRB:
- Suitable for centralized gateway deployment model
- Networks that have legacy switches without L3 VXLAN support and must use centralized gateways
- Small and medium scale data center deployments
Limitations:
- EVPN supports only IPv4 VTEP addresses.
Figure 1. Asymmetric EVPN IRB topology
Pre-configuration:
- Based on default configuration and initial FRR config (refer to FRRouting and config initialization)
- Create VLANs, bing IP addresses and interfaces (refer to VLAN & Inter-VLAN Routing article)
- Bind IP to Ethernet53 on switches (refer to Port IP addresses)
- Hosts are virtual machines that
Procedure :
- Create VxLANs
Aurora nba610-1:
admin@nba610-1:~$ sudo config vxlan add vtep 10.10.10.1 --> config vxlan add <vtepname> <src_ipv4> admin@nba610-1:~$ sudo config vxlan evpn_nvo add nvo vtep --> config vxlan evpn_nvo add <nvoname> <vtepname> admin@nba610-1:~$ sudo config vxlan map add vtep 100 100 --> config vxlan map add <vtepname> <vlanid> <vnid> admin@nba610-1:~$ sudo config vxlan map add vtep 200 200Aurora nba610-2:
admin@nba610-2:~$ sudo config vxlan add vtep 10.10.10.101 admin@nba610-2:~$ sudo config vxlan evpn_nvo add nvo vtep admin@nba610-2:~$ sudo config vxlan map add vtep 100 100 admin@nba610-2:~$ sudo config vxlan map add vtep 200 200- VNI (VxLAN Network Identifier) – uniquely identifies the VxLAN.
- VTEP (Virtual Tunnel End Point) – the entity that performs the encapsulation and decapsulation of packets.
- One switch can have only one VTEP with a unique identifier, such as the Loopback0 IP address.
- NVO (Network Virtualization Overlay) – only one NVO is allowed on one device.
- Announce EVPN routes.
Aurora nba610-1:
admin@nba610-1:~$ vtysh Hello, this is FRRouting (version 7.5.1-sonic). Copyright 1996-2005 Kunihiro Ishiguro, et al. nba610-1# configure terminal nba610-1(config)# router bgp 65100 nba610-1(config-router)# neighbor 10.0.1.0 remote-as 65100 nba610-1(config-router)# neighbor 10.0.1.0 description nba610-2 nba610-1(config-router)# address-family ipv4 unicast nba610-1(config-router-af)# network 10.10.10.1/32 nba610-1(config-router-af)# exit nba610-1(config-router)# address-family l2vpn evpn nba610-1(config-router-af)# neighbor 10.0.1.0 activate nba610-1(config-router-af)# advertise-all-vni nba610-1(config-router-af)# end nba610-1# write nba610-1# exitAurora nba610-2:
admin@nba610-2:~$ vtysh Hello, this is FRRouting (version 7.5.1-sonic). Copyright 1996-2005 Kunihiro Ishiguro, et al. nba610-2# configure terminal nba610-2(config)# router bgp 65100 nba610-2(config-router)# neighbor 10.0.1.1 remote-as 65100 nba610-2(config-router)# neighbor 10.0.1.1 description nba610-1 nba610-2(config-router)# address-family ipv4 unicast nba610-2(config-router-af)# network 10.10.10.101/32 nba610-2(config-router-af)# exit nba610-2(config-router)# address-family l2vpn evpn nba610-2(config-router-af)# neighbor 10.0.1.1 activate nba610-2(config-router-af)# advertise-all-vni nba610-2(config-router-af)# end nba610-2# write nba610-2# exit
Result
Check EVPN-VNI status.
Aurora nba610-1:
nba610-1# show evpn vni
VNI Type VxLAN IF # MACs # ARPs # Remote VTEPs Tenant VRF
100 L2 vtep-100 1 2 1 default
200 L2 vtep-200 1 2 1 default
nba610-1# show evpn vni detail
VNI: 100
Type: L2
Tenant VRF: default
VxLAN interface: vtep-100
VxLAN ifIndex: 68
Local VTEP IP: 10.10.10.1
Mcast group: 0.0.0.0
Remote VTEPs for this VNI:
10.10.10.101 flood: HER
Number of MACs (local and remote) known for this VNI: 1
Number of ARPs (IPv4 and IPv6, local and remote) known for this VNI: 2
Advertise-gw-macip: No
VNI: 200
Type: L2
Tenant VRF: default
VxLAN interface: vtep-200
VxLAN ifIndex: 69
Local VTEP IP: 10.10.10.1
Mcast group: 0.0.0.0
Remote VTEPs for this VNI:
10.10.10.101 flood: HER
Number of MACs (local and remote) known for this VNI: 1
Number of ARPs (IPv4 and IPv6, local and remote) known for this VNI: 2
Advertise-gw-macip: NoAurora nba610-2:
nba610-2# show evpn vni
VNI Type VxLAN IF # MACs # ARPs # Remote VTEPs Tenant VRF
200 L2 vtep-200 0 0 1 default
100 L2 vtep-100 0 0 1 default
nba610-2# show evpn vni detail
VNI: 200
Type: L2
Tenant VRF: default
VxLAN interface: vtep-200
VxLAN ifIndex: 72
Local VTEP IP: 10.10.10.101
Mcast group: 0.0.0.0
Remote VTEPs for this VNI:
10.10.10.1 flood: HER
Number of MACs (local and remote) known for this VNI: 0
Number of ARPs (IPv4 and IPv6, local and remote) known for this VNI: 0
Advertise-gw-macip: No
Advertise-svi-macip: No
VNI: 100
Type: L2
Tenant VRF: default
VxLAN interface: vtep-100
VxLAN ifIndex: 71
Local VTEP IP: 10.10.10.101
Mcast group: 0.0.0.0
Remote VTEPs for this VNI:
10.10.10.1 flood: HER
Number of MACs (local and remote) known for this VNI: 0
Number of ARPs (IPv4 and IPv6, local and remote) known for this VNI: 0
Advertise-gw-macip: No
Advertise-svi-macip: NoCheck BGP EVPN status.
Aurora nba610-1:
admin@nba610-1:~$ show vxlan vlanvnimap
+---------+-------+
| VLAN | VNI |
+=========+=======+
| Vlan100 | 1000 |
+---------+-------+
Total count : 1Aurora nba610-2:
admin@nba610-2:~$ show vxlan vlanvnimap
+---------+-------+
| VLAN | VNI |
+=========+=======+
| Vlan100 | 1000 |
+---------+-------+
Total count : 1