DHCP Relay Over L3 VPN for IPv4
Before configuring DHCP Relay, make sure DHCP server and client configurations are done.
Figure 7-13: DHCP Relay Over L3 VPN Configuration
DHCP Client
#configure terminal | Enter configure mode. |
(config)#interface xe2 | Enter interface mode. |
(config-if)#ip address dhcp | Enable DHCP on interface |
(config-if)#commit | Commit the candidate configuration to the running configuration |
PE1(DHCP Relay Agent)
#configure terminal | Enter configure mode. |
(config)#ip dhcp relay | By default this will be enabled. It starts the ip dhcp relay service. |
(config)#ip vrf vrf1 | Configuring non default vrf vrf1 |
(config-vrf)#rd 10:10 | Assign a route distinguisher to VRF |
(config-vrf)#route-target both 10:10 | Configure a route target for vrf1. |
(config-vrf)#ip dhcp relay address 11.11.0.1 | Configure DHCP server address. |
(config-vrf)#ip dhcp relay uplink l3vpn | configure IPv4 DHCP Relay over L3VPN. |
(config)#interface xe4 | Enter interface mode. |
(config-if)#ip vrf forwarding vrf1 | Configure vrf forwarding for vrf1 |
(config-if)#ip address 50.50.50.1/24 | Add IP address. |
(config-if)#ip dhcp relay | Configure DHCP relay for the interface connecting to client. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit from interface mode |
(config)#interface lo | Enter interface mode |
(config-if)#ip address 1.1.1.1/32 secondary | Set an IP address on the interface |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit from interface mode |
(config)#router ldp | Enter the Router LDP mode. |
(config-router)#router-id 1.1.1.1 | Configure an LDP router ID. |
(config-router)#exit | Exit from Router LDP mode |
(config)#interface xe1 | Enter interface mode |
(config-if)#ip address 10.1.1.1/24 | Add IP address. |
(config-if)#label-switching | Enable label switching on the interface |
(config-if)#enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#commit | Commit the candidate configuration to the running configuration |
(config-if)#exit | Exit from interface mode |
(config)#router ospf 100 | Enter the Router OSPF mode. |
(config-router)#network 1.1.1.1/32 area 0.0.0.0 | Advertise loopback address in OSPF. |
(config-router)#network 10.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#exit | Exit Router OSPF mode and return to Configure mode. |
(config)# router bgp 100 | Enter the Router BGP mode, ASN: 100 |
(config-router)# bgp router-id 1.1.1.1 | Configure a fixed Router ID (1.1.1.1) |
(config-router)# neighbor 3.3.3.3 remote-as 100 | Configuring PE2 as iBGP neighbor using it's loopback IP |
(config-router)# neighbor 3.3.3.3 update-source lo | Source of routing updates as loopback |
(config-router)# address-family ipv4 unicast | Entering into IPV4 unicast address family |
(config-router-af)# neighbor 3.3.3.3 activate | Activate the neighbor in the IPV4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# address-family vpnv4 unicast | Entering into address family mode as vpnv4 |
(config-router-af)# neighbor 3.3.3.3 activate | Activate the neighbor in the vpnv4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# address-family ipv4 vrf vrf1 | Entering into address family mode as ipv4 vrf vrf1 |
(config-router-af)# redistribute connected | Redistribute connected routes. |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# commit | Commit the candidate configuration to the running configuration |
P
#configure terminal | Enter configure mode. |
(config)#interface lo | Enter interface mode |
(config-if)#ip address 2.2.2.2/32 secondary | Set an IP address on the interface |
(config-if)#exit | Exit from interface mode |
(config)#router ldp | Enter the Router LDP mode. |
(config-router)#router-id 2.2.2.2 | Configure an LDP router ID. |
(config-router)#exit | Exit from Router LDP mode |
(config)#interface xe14 | Enter interface mode |
(config-if)# ip address 20.1.1.1/24 | Add IP address. |
(config-if)# label-switching | Enable label switching on the interface |
(config-if)# enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#interface xe1 | Enter interface mode |
(config-if)# ip address 10.1.1.2/24 | Add IP address. |
(config-if)# label-switching | Enable label switching on the interface |
(config-if)# enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#router ospf 100 | Enter the Router OSPF mode. |
(config-router)#network 3.3.3.3/32 area 0.0.0.0 | Advertise loopback address in OSPF. |
(config-router)#network 20.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#network 10.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#exit | Exit Router OSPF mode and return to Configure mode. |
(config)# commit | Commit the candidate configuration to the running configuration |
PE2
#configure terminal | Enter configure mode. |
(config)#ip vrf vrf1 | Configuring non default vrf vrf1 |
(config-vrf)# rd 10:10 | Assign a route distinguisher to VRF |
(config-vrf)# route-target both 10:10 | Configure a route target for vrf1. |
(config)#interface xe48 | Enter interface mode. |
(config-if)#ip vrf forwarding vrf1 | Configure vrf forwarding for vrf1 |
(config-if)# commit | Commit the candidate config |
(config-if)#ip address 11.11.0.2/24 | Add IP address. |
(config-if)#exit | Exit from interface mode |
(config)#interface lo | Enter interface mode |
(config-if)#ip address 3.3.3.3/32 secondary | Set an IP address on the interface |
(config-if)#exit | Exit from interface mode |
(config)#router ldp | Enter the Router LDP mode. |
(config-router)#router-id 3.3.3.3 | Configure an LDP router ID. |
(config-router)#exit | Exit from Router LDP mode |
(config)#interface xe14 | Enter interface mode |
(config-if)# ip address 20.1.1.2/24 | Add IP address. |
(config-if)# label-switching | Enable label switching on the interface |
(config-if)# enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#router ospf 100 | Enter the Router OSPF mode. |
(config-router)#network 3.3.3.3/32 area 0.0.0.0 | Advertise loopback address in OSPF. |
(config-router)#network 20.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#exit | Exit Router OSPF mode and return to Configure mode. |
(config)# router bgp 100 | Enter the Router BGP mode, ASN: 100 |
(config-router)# bgp router-id 3.3.3.3 | Configure a fixed Router ID (3.3.3.3) |
(config-router)# neighbor 1.1.1.1 remote-as 100 | Configuring PE1 as iBGP neighbor using it's loopback IP |
(config-router)# neighbor 1.1.1.1 update-source lo | Source of routing updates as loopback |
(config-router)# address-family ipv4 unicast | Entering into IPV4 unicast address family |
(config-router-af)# neighbor 1.1.1.1 activate | Activate the neighbor in the IPV4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# address-family vpnv4 unicast | Entering into address family mode as vpnv4 |
(config-router-af)# neighbor 1.1.1.1 activate | Activate the neighbor in the vpnv4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# address-family ipv4 vrf vrf1 | Entering into address family mode as ipv4 vrf vrf1 |
(config-router-af)# redistribute connected | Redistribute connected routes. |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# commit | Commit the candidate configuration to the running configuration |
Validation
PE1 (DHCP Relay Agent)
PE1#show running-config dhcp
ip vrf vrf1
ip dhcp relay address 11.11.0.1
ip dhcp relay uplink l3vpn
interface xe4
ip dhcp relay
PE1#show ip dhcp relay
DHCP relay service is Enabled.
VRF Name: vrf1
Option 82: Disabled
DHCP Servers configured: 11.11.0.1
Interface Uplink/Downlink
--------- -------------
xe4 Downlink
l3vpn uplink
Incoming DHCPv4 packets which already contain relay agent option are FORWARDED u
nchanged.
PE1#show ip dhcp relay address
VRF Name: vrf1
DHCP Servers configured: 11.11.0.1
Incoming DHCPv4 packets which already contain relay agent option are FORWARDED u
nchanged.
DHCP Client
#show ip interface brief | include xe2
xe5 *50.50.50.2 up up
DHCP Relay Over L3 VPN for IPv6
Before configuring DHCP Relay, make sure DHCP server and client configurations are done.
.
Figure 7-14: DHCP Relay Over L3 VPN Configuration
DHCP Client
#configure terminal | Enter configure mode. |
(config)#interface xe2 | Enter interface mode. |
(config-if)#ipv6 address dhcp | Enable DHCP on interface |
(config-if)#commit | Commit the candidate configuration to the running configuration |
PE1(DHCP Relay Agent)
#configure terminal | Enter configure mode. |
(config)#ipv6 dhcp relay | By default this will be enabled. It starts the ipv6 dhcp relay service. |
(config)#ip vrf vrf1 | Configuring non default vrf vrf1 |
(config-vrf)#rd 10:10 | Assign a route distinguisher to VRF |
(config-vrf)#route-target both 10:10 | Configure a route target for vrf1. |
(config-vrf)#ipv6 dhcp relay address 2002::1 | Configure DHCP server address. |
(config-vrf)#ipv6 dhcp relay uplink l3vpn | configure IPv6 DHCP Relay over L3VPN. |
(config)#interface xe4 | Enter interface mode. |
(config-if)#ip vrf forwarding vrf1 | Configure vrf forwarding for vrf1 |
(config-if)# ipv6 address 2001::1/64 | Add IPv6 address. |
(config-if)#ipv6 dhcp relay | Configure DHCP relay for the interface connecting to client. |
(config-if)#exit | Exit from interface mode |
(config)#interface lo | Enter interface mode |
(config-if)#ip address 1.1.1.1/32 secondary | Set an IP address on the interface |
(config-if)#exit | Exit from interface mode |
(config)#router ldp | Enter the Router LDP mode. |
(config-router)#router-id 1.1.1.1 | Configure an LDP router ID. |
(config-router)#exit | Exit from Router LDP mode |
(config)#interface xe1 | Enter interface mode |
(config-if)# ip address 10.1.1.1/24 | Add IP address. |
(config-if)# label-switching | Enable label switching on the interface |
(config-if)# enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#router ospf 100 | Enter the Router OSPF mode. |
(config-router)#network 1.1.1.1/32 area 0.0.0.0 | Advertise loopback address in OSPF. |
(config-router)#network 10.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#exit | Exit Router OSPF mode and return to Configure mode. |
(config)#router bgp 100 | Enter the Router BGP mode, ASN: 100 |
(config-router)#bgp router-id 1.1.1.1 | Configure a fixed Router ID (1.1.1.1) |
(config-router)#neighbor 3.3.3.3 remote-as 100 | Configuring PE2 as iBGP neighbor using it's loopback IP |
(config-router)#neighbor 3.3.3.3 update-source lo | Source of routing updates as loopback |
(config-router)#address-family ipv4 unicast | Entering into IPV4 unicast address family |
(config-router-af)#neighbor 3.3.3.3 activate | Activate the neighbor in the IPV4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#address-family vpnv4 unicast | Entering into address family mode as vpnv4 |
(config-router-af)#neighbor 3.3.3.3 activate | Activate the neighbor in the vpnv4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#address-family vpnv6 unicast | Entering into address family mode as vpnv6 |
(config-router-af)#neighbor 3.3.3.3 activate | Activate the neighbor in the vpnv6 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# address-family ipv4 vrf vrf1 | Entering into address family mode as ipv4 vrf vrf1 |
(config-router-af)#redistribute connected | Redistribute connected routes. |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)# address-family ipv6 vrf vrf1 | Entering into address family mode as ipv6 vrf vrf1 |
(config-router-af)#redistribute connected | Redistribute connected routes. |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#commit | Commit the candidate configuration to the running configuration |
P
#configure terminal | Enter configure mode. |
(config)#interface lo | Enter interface mode |
(config-if)#ip address 2.2.2.2/32 secondary | Set an IP address on the interface |
(config-if)#exit | Exit from interface mode |
(config)#router ldp | Enter the Router LDP mode. |
(config-router)#router-id 2.2.2.2 | Configure an LDP router ID. |
(config-router)#exit | Exit from Router LDP mode |
(config)#interface xe14 | Enter interface mode |
(config-if)#ip address 20.1.1.1/24 | Add IP address. |
(config-if)#label-switching | Enable label switching on the interface |
(config-if)#enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#interface xe1 | Enter interface mode |
(config-if)#ip address 10.1.1.2/24 | Add IP address. |
(config-if)#label-switching | Enable label switching on the interface |
(config-if)#enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#router ospf 100 | Enter the Router OSPF mode. |
(config-router)#network 3.3.3.3/32 area 0.0.0.0 | Advertise loopback address in OSPF. |
(config-router)#network 20.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#network 10.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#exit | Exit Router OSPF mode and return to Configure mode. |
(config)# commit | Commit the candidate configuration to the running configuration |
PE2
#configure terminal | Enter configure mode. |
(config)#ip vrf vrf1 | Configuring non default vrf vrf1 |
(config-vrf)#rd 10:10 | Assign a route distinguisher to VRF |
(config-vrf)#route-target both 10:10 | Configure a route target for vrf1. |
(config)#interface xe48 | Enter interface mode. |
(config-if)#ip vrf forwarding vrf1 | Configure vrf forwarding for vrf1 |
(config-if)#commit | Commit the candidate config |
(config-if)#ipv6 address 2002::2/64 | Add IPv6 address. |
(config-if)#exit | Exit from interface mode |
(config)#interface lo | Enter interface mode |
(config-if)#ip address 3.3.3.3/32 secondary | Set an IP address on the interface |
(config-if)#exit | Exit from interface mode |
(config)#router ldp | Enter the Router LDP mode. |
(config-router)#router-id 3.3.3.3 | Configure an LDP router ID. |
(config-router)#exit | Exit from Router LDP mode |
(config)#interface xe14 | Enter interface mode |
(config-if)#ip address 20.1.1.2/24 | Add IP address. |
(config-if)#label-switching | Enable label switching on the interface |
(config-if)#enable-ldp ipv4 | Enable IPv4 LDP configuration on the interface. |
(config-if)#exit | Exit from interface mode |
(config)#router ospf 100 | Enter the Router OSPF mode. |
(config-router)#network 3.3.3.3/32 area 0.0.0.0 | Advertise loopback address in OSPF. |
(config-router)#network 20.1.1.0/24 area 0.0.0.0 | Advertise network address in OSPF. |
(config-router)#exit | Exit Router OSPF mode and return to Configure mode. |
(config)#router bgp 100 | Enter the Router BGP mode, ASN: 100 |
(config-router)#bgp router-id 3.3.3.3 | Configure a fixed Router ID (3.3.3.3) |
(config-router)#neighbor 1.1.1.1 remote-as 100 | Configuring PE1 as iBGP neighbor using it's loopback IP |
(config-router)#neighbor 1.1.1.1 update-source lo | Source of routing updates as loopback |
(config-router)#address-family ipv4 unicast | Entering into IPV4 unicast address family |
(config-router-af)#neighbor 1.1.1.1 activate | Activate the neighbor in the IPV4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#address-family vpnv4 unicast | Entering into address family mode as vpnv4 |
(config-router-af)#neighbor 1.1.1.1 activate | Activate the neighbor in the vpnv4 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#address-family vpnv6 unicast | Entering into address family mode as vpnv6 |
(config-router-af)#neighbor 1.1.1.1 activate | Activate the neighbor in the vpnv6 address family |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#address-family ipv4 vrf vrf1 | Entering into address family mode as ipv4 vrf vrf1 |
(config-router-af)#redistribute connected | Redistribute connected routes. |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#address-family ipv6 vrf vrf1 | Entering into address family mode as ipv6 vrf vrf1 |
(config-router-af)#redistribute connected | Redistribute connected routes. |
(config-router-af)#exit | Exiting of Address family mode |
(config-router)#commit | Commit the candidate configuration to the running configuration |
Validation
PE1 (DHCP Relay Agent)
PE1#show running-config dhcp
ip vrf vrf1
ipv6 dhcp relay address 2002::1
ipv6 dhcp relay uplink l3vpn
interface xe4
ipv6 dhcp relay
PE1#show ipv6 dhcp relay
IPv6 DHCP relay service is Enabled.
VRF Name: vrf1
Option 82: Enabled
DHCPv6 Servers configured: 2002::1
DHCPv6 IA_PD Route injection: Disabled
Interface Uplink/Downlink
--------- -------------
xe4 Downlink
l3vpn uplink
PE1#show ip dhcp relay address
VRF Name: vrf1
DHCPv6 Servers configured: 2002::1
DHCP Client
#show ipv6 interface brief | include xe2
xe5 *2001::200 up up
Last modified date: 10/19/2023