mini鵝的天地

VRF（Virtual Routing and Forwarding）
將一台實體路由器虛擬為多台路由器，且每台虛擬路由器皆有獨立的路由表在運作，並達到隔離其他虛擬路由器。

定義虛擬路由器或路由名稱
ip vrf vrf-name
ip vrf forwarding vrf-name

定義vrf 
vrf definition vrf-name
  rd 100:1  
  address-family ipv4
  exit-address-family

建立OSPF VRF
router ospf process-id vrf vrf-name
建立EIGRP VRF
router eigrp id
 address-family ipv4 vrf vrf-name
建立RIP VRF
router rip
 address-family ipv4 vrf vrf-name

*在介面啟動VRF，可能會使介面IP被移除

查看有啟動VRF的instnace及套用的介面
show ip vrf
查看VRF的路由表
show ip route vrf vrf-name
查看EIGRP VRF啟動狀態
show ip protocols vrf vrf-name
查看VRF EIGRP鄰居
show ip eigrp vrf vrf-name neighbors
Ping vrf 應用
ping vrf vrf-name x.x.x.x

範例：

ip routing

vrf definition MGMT
 address-family ipv4
 exit-address-family

int vlan 2
 ip vrf forwarding MGMT
 ip address 172.16.2.253 255.255.255.0

ip route vrf MGMT 0.0.0.0 0.0.0.0 172.16.2.254

補充：

若使用IPv6來做vrf時，跳出以下指令

(config-vrf)#address-family ipv6
% VRF address family ipv6 is not supported or not enabled
% Can’t activate address-family ‘ipv6’

則需使用以下指令來解決

(config)#mls ipv6 vrf     /開啟ipv6 vrf

(config)#vrf upgrade-cli multi-af-mode {common-policies | non-common-policies} [vrf vrf-name]   

範例：

1.未下更正指令時，設定如下

interface Loopback10
 ip vrf forwarding test
 ipv6 address 2404:A800::1/64

2.設定

(config)#vrf upgrade-cli multi-af-mode non-common-policies vrf test

或

(config)#vrf upgrade-cli multi-af-mode common-policies

You are about to upgrade to the multi-AF VRF syntax commands.

Are you sure ? [yes]:
Number of VRFs upgraded: 1

3.查看之後指令變化，IPv6的IP Address被清除之外，ip vrf forwarding指令變成vrf forwarding

interface Loopback10
 vrf forwarding test

4.需手動再新增加回IPv6的IP Address
 (config-if)#ipv6 address 2404:A800::1/64

參考資料

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_l3_vpns/configuration/xe-3s/mp-l3-vpns-xe-3s-book/mp-vpn-ipv4-ipv6.html