Example for Configuring Three-Segment VXLAN to Implement Layer 2 Interworking

This section provides an example for configuring three-segment VXLAN tunnels to enable Layer 2 communication between VMs that belong to the different DCs.

Networking Requirements

On the network shown in Figure 1, BGP EVPN is configured within DC A and DC B to establish VXLAN tunnels. BGP EVPN is also configured on Leaf 2 and Leaf 3 to establish a VXLAN tunnel between them. To enable communication between VM 1 and VM 2, implement Layer 2 communication between DC A and DC B. In this example, the VXLAN tunnel in DC A uses the VNI 10, and that in DC B uses the VNI 20. VNI conversion must be Implemented before establishing a VXLAN tunnel between Leaf 2 and Leaf 3.

Figure 1 Configuring three-segment VXLAN to implement Layer 2 interworking

Interfaces 1 and 2 in this example represent GE 0/1/0 and GE 0/1/8, respectively.

**Table 1** Interface IP addresses
Device	Interface	IP Address	Device	Interface	IP Address
Spine 1	GE 0/1/0	192.168.10.1/24	Spine 2	GE 0/1/0	192.168.30.1/24
Spine 1	GE 0/1/8	192.168.20.1/24	Spine 2	GE 0/1/8	192.168.40.1/24
Leaf 1	GE 0/1/0	192.168.10.2/24	Leaf 4	GE 0/1/0	192.168.40.2/24
	GE 0/1/8	-		GE 0/1/8	-
	Loopback 1	1.1.1.1/32		Loopback 1	4.4.4.4/32
Leaf 2	GE 0/1/0	192.168.20.2/24	Leaf 3	GE 0/1/0	192.168.30.2/24
	GE 0/1/8	192.168.50.1/24		GE 0/1/8	192.168.50.2/24
	Loopback 1	2.2.2.2/32		Loopback 1	3.3.3.3/32

Configuration Roadmap

The configuration roadmap is as follows:

Assign an IP address to each interface.
Configure an IGP to allow devices to communicate with each other.
Configure static routes to achieve interworking between DCs.
Configure BGP EVPN within DC A and DC B to establish VXLAN tunnels.
Configure BGP EVPN on Leaf 2 and Leaf 3 to establish a VXLAN tunnel between them.
Configure Leaf 2 and Leaf 3 to advertise routes that are re-originated by the EVPN address family to BGP EVPN peers.

Data Preparation

To complete the configuration, you need the following data:

VLAN IDs of the VMs
BD IDs
VNI IDs associated with BDs within DC A and DC B
Number of the AS to which DC A and DC B belong
Name of the SHG to which Leaf 2 and Leaf 3 belong

Procedure

Assign an IP address to each interface (including the loopback interface) on each node.
For configuration details, see "Configuration Files" in this section.
Configure an IGP. In this example, OSPF is used.
For configuration details, see "Configuration Files" in this section.
Configure static routes to achieve interworking between DCs.
For configuration details, see "Configuration Files" in this section.

Configure BGP EVPN within DC A and DC B to create VXLAN tunnels.

Configuring service access points on Leaf 1 and Leaf 4.

# Configure Leaf 1.

[~Leaf1] bridge-domain 10
[*Leaf1-bd10] quit
[*Leaf1] interface GE 0/1/8.1 mode l2
[*Leaf1-GE0/1/8.1] encapsulation dot1q vid 10
[*Leaf1-GE0/1/8.1] rewrite pop single
[*Leaf1-GE0/1/8.1] bridge-domain 10
[*Leaf1-GE0/1/8.1] quit
[*Leaf1] commit

Repeat these steps for Leaf 4. For configuration details, see "Configuration Files" in this section.

Configure BGP EVPN peer relationships between Leaf 1 and Leaf 2 in DC A and between Leaf 3 and Leaf 4 in DC B.

# Configure a BGP EVPN peer relationship on Leaf 1.

[~Leaf1] bgp 100
[*Leaf1-bgp] peer 2.2.2.2 as-number 100
[*Leaf1-bgp] peer 2.2.2.2 connect-interface LoopBack 1
[*Leaf1-bgp] l2vpn-family evpn
[*Leaf1-bgp-af-evpn] peer 2.2.2.2 enable
[*Leaf1-bgp-af-evpn] peer 2.2.2.2 advertise encap-type vxlan
[*Leaf1-bgp-af-evpn] quit
[*Leaf1-bgp] quit
[*Leaf1] commit

Repeat these steps for Leaf 2, Leaf 3, and Leaf 4. For configuration details, see "Configuration Files" in this section.

Configure EVPN an instance on each leaf node.

# Configure Leaf 1.

[~Leaf1] evpn vpn-instance evrf1 bd-mode
[*Leaf1-evpn-instance-evrf1] route-distinguisher 10:1
[*Leaf1-evpn-instance-evrf1] vpn-target 11:1
[*Leaf1-evpn-instance-evrf1] quit
[*Leaf1] bridge-domain 10
[*Leaf1-bd10] vxlan vni 10 split-horizon-mode
[*Leaf1-bd10] evpn binding vpn-instance evrf1
[*Leaf1-bd10] quit
[*Leaf1] commit

Repeat these steps for Leaf 2, Leaf 3, and Leaf 4. For configuration details, see "Configuration Files" in this section.

Configure an ingress replication list on each leaf node.
# Configure Leaf 1.
```
[~Leaf1] interface nve 1
[*Leaf1-Nve1] source 1.1.1.1
[*Leaf1-Nve1] vni 10 head-end peer-list protocol bgp
[*Leaf1-Nve1] quit
[*Leaf1] commit
```
Repeat these steps for Leaf 2, Leaf 3, and Leaf 4. For configuration details, see "Configuration Files" in this section.

Configure BGP EVPN on Leaf 2 and Leaf 3 to establish a VXLAN tunnel between them.

Configure a BGP EVPN peer relationship.

# Configure Leaf 2.

[~Leaf2] bgp 100
[*Leaf2-bgp] peer 3.3.3.3 as-number 200
[*Leaf2-bgp] peer 3.3.3.3 connect-interface LoopBack 1
[*Leaf2-bgp] peer 3.3.3.3 ebgp-max-hop 255
[*Leaf2-bgp] network 2.2.2.2 32
[*Leaf2-bgp] l2vpn-family evpn
[*Leaf2-bgp-af-evpn] peer 3.3.3.3 enable
[*Leaf2-bgp-af-evpn] peer 3.3.3.3 advertise encap-type vxlan
[*Leaf2-bgp-af-evpn] quit
[*Leaf2-bgp] quit
[*Leaf2] commit

# Configure Leaf 3.

[~Leaf3] bgp 200
[*Leaf3-bgp] peer 2.2.2.2 as-number 100
[*Leaf3-bgp] peer 2.2.2.2 connect-interface LoopBack 1
[*Leaf3-bgp] peer 2.2.2.2 ebgp-max-hop 255
[*Leaf3-bgp] network 3.3.3.3 32
[*Leaf3-bgp] l2vpn-family evpn
[*Leaf3-bgp-af-evpn] peer 2.2.2.2 enable
[*Leaf3-bgp-af-evpn] peer 2.2.2.2 advertise encap-type vxlan
[*Leaf3-bgp-af-evpn] quit
[*Leaf3-bgp] quit
[*Leaf3] commit

Configure Leaf 2 and Leaf 3 to advertise routes that are re-originated by the EVPN address family to BGP EVPN peers.

Configure an SHG to which the BGP EVPN peers belong.

# Configure Leaf 2.

[~Leaf2] bgp 100
[~Leaf2-bgp] l2vpn-family evpn
[~Leaf2-bgp-af-evpn] peer 3.3.3.3 split-group sg1
[*Leaf2-bgp-af-evpn] commit

# Configure Leaf 3.

[~Leaf3] bgp 200
[~Leaf3-bgp] l2vpn-family evpn
[~Leaf3-bgp-af-evpn] peer 2.2.2.2 split-group sg1
[*Leaf3-bgp-af-evpn] commit

Enable the function to re-originate MAC routes.

# Configure Leaf 2.

[~Leaf2-bgp-af-evpn] peer 1.1.1.1 import reoriginate
[*Leaf2-bgp-af-evpn] peer 1.1.1.1 advertise route-reoriginated evpn mac
[*Leaf2-bgp-af-evpn] peer 3.3.3.3 import reoriginate
[*Leaf2-bgp-af-evpn] peer 3.3.3.3 advertise route-reoriginated evpn mac
[*Leaf2-bgp-af-evpn] quit
[*Leaf2-bgp] quit
[*Leaf2] commit

# Configure Leaf 3.

[~Leaf3-bgp-af-evpn] peer 4.4.4.4 import reoriginate
[*Leaf3-bgp-af-evpn] peer 4.4.4.4 advertise route-reoriginated evpn mac
[*Leaf3-bgp-af-evpn] peer 2.2.2.2 import reoriginate
[*Leaf3-bgp-af-evpn] peer 2.2.2.2 advertise route-reoriginated evpn mac
[*Leaf3-bgp-af-evpn] quit
[*Leaf3-bgp] quit
[*Leaf3] commit

Verify the configuration.

Run the display vxlan tunnel command on each leaf node to view information about the VXLAN tunnels. The following example uses the command output on Leaf 2. The command output shows that the VXLAN tunnels are Up.

[~Leaf2] display vxlan tunnel
Number of vxlan tunnel : 2
Tunnel ID   Source                Destination           State  Type     Uptime
-----------------------------------------------------------------------------------
4026531924  2.2.2.2               1.1.1.1               up     dynamic  00:39:19  
4026531925  2.2.2.2               3.3.3.3               up     dynamic  00:39:09

Run the display vxlan peer command on Leaf 2 to view information about the VXLAN peers.

[~Leaf2] display vxlan peer
Number of peers : 2
Vni ID    Source                  Destination            Type      Out Vni ID
-------------------------------------------------------------------------------
10        2.2.2.2                 1.1.1.1                dynamic   10         
10        2.2.2.2                 3.3.3.3                dynamic   20

After the preceding configurations are complete, Layer 2 communication can be implemented between VM 1 and VM 2.

Configuration Files

Spine 1 configuration file

#
sysname Spine1
#
interface GE0/1/0
 undo shutdown  
 ip address 192.168.10.1 255.255.255.0
#               
interface GE0/1/8
 undo shutdown  
 ip address 192.168.20.1 255.255.255.0
#               
ospf 1          
 area 0.0.0.0   
  network 192.168.10.0 0.0.0.255
  network 192.168.20.0 0.0.0.255
#               
return

Leaf 1 configuration file

#
sysname Leaf1
#
evpn vpn-instance evrf1 bd-mode
 route-distinguisher 10:1
 vpn-target 11:1 export-extcommunity
 vpn-target 11:1 import-extcommunity
#
bridge-domain 10
 vxlan vni 10 split-horizon-mode
 evpn binding vpn-instance evrf1
#               
interface GE0/1/0
 undo shutdown  
 ip address 192.168.10.2 255.255.255.0
#               
interface GE0/1/8
 undo shutdown       
#               
interface GE0/1/8.1 mode l2
 encapsulation dot1q vid 10
 rewrite pop single
 bridge-domain 10
#               
interface LoopBack1
 ip address 1.1.1.1 255.255.255.255
#               
interface Nve1  
 source 1.1.1.1 
 vni 10 head-end peer-list protocol bgp
#               
bgp 100
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 connect-interface LoopBack1
 #
 ipv4-family unicast
  peer 2.2.2.2 enable
 #              
 l2vpn-family evpn
  undo policy vpn-target
  peer 2.2.2.2 enable
  peer 2.2.2.2 advertise encap-type vxlan
#               
ospf 1          
 area 0.0.0.0   
  network 1.1.1.1 0.0.0.0
  network 192.168.10.0 0.0.0.255
#               
return

Leaf 2 configuration file

#
sysname Leaf2
#
evpn vpn-instance evrf1 bd-mode
 route-distinguisher 10:1
 vpn-target 11:1 export-extcommunity
 vpn-target 11:1 import-extcommunity
#
bridge-domain 10
 vxlan vni 10 split-horizon-mode
 evpn binding vpn-instance evrf1
#                         
interface GE0/1/0
 undo shutdown  
 ip address 192.168.20.2 255.255.255.0
#               
interface GE0/1/8
 undo shutdown  
 ip address 192.168.50.1 255.255.255.0
#               
interface LoopBack1
 ip address 2.2.2.2 255.255.255.255
#               
interface Nve1  
 source 2.2.2.2 
 vni 10 head-end peer-list protocol bgp
#               
bgp 100
 peer 1.1.1.1 as-number 100
 peer 1.1.1.1 connect-interface LoopBack1
 peer 3.3.3.3 as-number 200
 peer 3.3.3.3 ebgp-max-hop 255
 peer 3.3.3.3 connect-interface LoopBack1
 #
 ipv4-family unicast
  network 2.2.2.2 255.255.255.255
  peer 1.1.1.1 enable
  peer 3.3.3.3 enable
 #              
 l2vpn-family evpn
  undo policy vpn-target
  peer 1.1.1.1 enable
  peer 1.1.1.1 advertise encap-type vxlan
  peer 1.1.1.1 import reoriginate
  peer 1.1.1.1 advertise route-reoriginated evpn mac
  peer 3.3.3.3 enable
  peer 3.3.3.3 advertise encap-type vxlan
  peer 3.3.3.3 import reoriginate
  peer 3.3.3.3 advertise route-reoriginated evpn mac
  peer 3.3.3.3 split-group sg1
#
ospf 1          
 area 0.0.0.0   
  network 2.2.2.2 0.0.0.0
  network 192.168.20.0 0.0.0.255
#
ip route-static 3.3.3.3 255.255.255.255 192.168.50.2
#               
return

Spine 2 configuration file

#
sysname Spine2
#
interface GE0/1/0
 undo shutdown  
 ip address 192.168.30.1 255.255.255.0
#               
interface GE0/1/8
 undo shutdown  
 ip address 192.168.40.1 255.255.255.0
#               
ospf 1          
 area 0.0.0.0   
  network 192.168.30.0 0.0.0.255
  network 192.168.40.0 0.0.0.255
#               
return

Leaf 3 configuration file

#
sysname Leaf3
#
evpn vpn-instance evrf1 bd-mode
 route-distinguisher 10:1
 vpn-target 11:1 export-extcommunity
 vpn-target 11:1 import-extcommunity
#
bridge-domain 10
 vxlan vni 20 split-horizon-mode
 evpn binding vpn-instance evrf1
#               
interface GE0/1/0
 undo shutdown  
 ip address 192.168.30.2 255.255.255.0
#               
interface GE0/1/8
 undo shutdown  
 ip address 192.168.50.2 255.255.255.0

#               
interface LoopBack1
 ip address 3.3.3.3 255.255.255.255
#               
interface Nve1  
 source 3.3.3.3 
 vni 20 head-end peer-list protocol bgp
#               
bgp 200
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 ebgp-max-hop 255
 peer 2.2.2.2 connect-interface LoopBack1
 peer 4.4.4.4 as-number 200
 peer 4.4.4.4 connect-interface LoopBack1
 #
 ipv4-family unicast
  network 3.3.3.3 255.255.255.255
  peer 2.2.2.2 enable
  peer 4.4.4.4 enable
 #              
 l2vpn-family evpn
  undo policy vpn-target
  peer 2.2.2.2 enable
  peer 2.2.2.2 advertise encap-type vxlan
  peer 2.2.2.2 import reoriginate
  peer 2.2.2.2 advertise route-reoriginated evpn mac
  peer 2.2.2.2 split-group sg1
  peer 4.4.4.4 enable
  peer 4.4.4.4 advertise encap-type vxlan
  peer 4.4.4.4 import reoriginate
  peer 4.4.4.4 advertise route-reoriginated evpn mac
#               
ospf 1          
 area 0.0.0.0   
  network 3.3.3.3 0.0.0.0
  network 192.168.30.0 0.0.0.255
#
ip route-static 2.2.2.2 255.255.255.255 192.168.50.1
#               
return

Leaf 4 configuration file

#
sysname Leaf4
#
evpn vpn-instance evrf1 bd-mode
 route-distinguisher 10:1
 vpn-target 11:1 export-extcommunity
 vpn-target 11:1 import-extcommunity
#
bridge-domain 10
 vxlan vni 20 split-horizon-mode
 evpn binding vpn-instance evrf1
#               
interface GE0/1/0
 undo shutdown  
 ip address 192.168.40.2 255.255.255.0
#                              
interface GE0/1/8
 undo shutdown       
#               
interface GE0/1/8.1 mode l2
 encapsulation dot1q vid 10
 rewrite pop single
 bridge-domain 10
#               
interface LoopBack1
 ip address 4.4.4.4 255.255.255.255
#               
interface Nve1  
 source 4.4.4.4 
 vni 20 head-end peer-list protocol bgp
#               
bgp 200
 peer 3.3.3.3 as-number 200
 peer 3.3.3.3 connect-interface LoopBack1
 #
 ipv4-family unicast
  peer 3.3.3.3 enable
 #              
 l2vpn-family evpn
  undo policy vpn-target
  peer 3.3.3.3 enable
  peer 3.3.3.3 advertise encap-type vxlan
#               
ospf 1          
 area 0.0.0.0   
  network 4.4.4.4 0.0.0.0
  network 192.168.40.0 0.0.0.255
#               
return