- RFC7348은 Broadcast, Unknown packet을 multicast packet으로 encapsulation하여 PIM router에서 Flooding하여 peer VTEP가 수신할 수 있는 방식을 설명한다.
- 하지만 많은 사업자들이 IP multicast를 지원하지 않는 경우가 있기 때문에 multicast가 아닌 unicast로 encapsulation하는 방식도 지원하는데 이를 HER(Head End Replication) 이라고 한다.
이번 포스트에서는 Unicast Based(HEF) VXLAN을 시험해보도록 한다.
Test Env.
- GNS3 Local Server (1.5.2)
- vEOS x 2 (4.16, VirtualBox, 1.5 GB)
- c7200 x 1 (15.2(4)M8, Dynamips)
- Ostinato (VirtualBox, 256 MB)
Test
HER VXLAN은 underday network으로 IP multicast를 사용하지 않으므로 Test network에 PIM 설정을 생략한다.
Broadcast tunneling packet
Destination IP address와 MAC address가 unicast address를 사용하고 있다.
Unknown Unicast tunneling packet
Destination IP address와 MAC address가 unicast address를 사용하고 있다.
Known unicast tunneling packet
vEOS-1#show mac address-table
Mac Address Table
------------------------------------------------------------------
Vlan Mac Address Type Ports Moves Last Move
---- ----------- ---- ----- ----- ---------
10 0000.0000.0011 DYNAMIC Et2 47 37 seconds ago
10 0000.0000.0022 DYNAMIC Vx1 1 37 seconds ago
Total Mac Addresses for this criterion: 2
Multicast Mac Address Table
------------------------------------------------------------------
Vlan Mac Address Type Ports
---- ----------- ---- -----
Total Mac Addresses for this criterion: 0
VXLAN 관련 확인
vxlan을 통행 learning된 mac address-table 확인
vEOS-1#show vxlan address-table
Vxlan Mac Address Table
----------------------------------------------------------------------
Vlan Mac Address Type Prt Vtep Moves Last Move
---- ----------- ---- --- ---- ----- ---------
10 0000.0000.0022 DYNAMIC Vx1 2.2.2.2 1 0:00:54 ago
Total Remote Mac Addresses for this criterion: 1
vxlan를 통해 수신된 peer VTEP list
vEOS-1#show vxlan vtep
Remote vteps for Vxlan1:
2.2.2.2
Total number of remote vteps: 1
Configuration
vEOS-1
! Command: show running-config
! device: vEOS-1 (vEOS, EOS-4.16.6M)
!
! boot system flash:/vEOS-lab.swi
!
transceiver qsfp default-mode 4x10G
!
no lldp run
!
hostname vEOS-1
!
spanning-tree mode mstp
!
no aaa root
!
vlan 10
!
interface Ethernet1
no switchport
ip address 10.1.1.2/30
!
interface Ethernet2
switchport access vlan 10
!
interface Ethernet3
!
interface Ethernet4
!
interface Loopback0
ip address 1.1.1.1/32
!
interface Management1
!
interface Vxlan1
vxlan source-interface Loopback0
vxlan udp-port 4789
vxlan vlan 10 vni 4096
vxlan flood vtep 2.2.2.2
!
ip routing
!
router ospf 1
router-id 1.1.1.1
network 1.1.1.1/32 area 0.0.0.0
network 10.1.1.0/30 area 0.0.0.0
max-lsa 12000
!
!
end
c7200
Building configuration...
Current configuration : 1343 bytes
!
! Last configuration change at 17:24:29 UTC Fri Sep 23 2016
upgrade fpd auto
version 15.2
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname c7200
!
boot-start-marker
boot-end-marker
!
!
!
no aaa new-model
no ip icmp rate-limit unreachable
!
!
!
!
!
!
no ip domain lookup
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
redundancy
!
!
ip tcp synwait-time 5
!
!
!
!
!
!
!
!
!
!
interface Loopback0
ip address 5.5.5.5 255.255.255.255
!
interface FastEthernet0/0
no ip address
shutdown
duplex half
!
interface FastEthernet1/0
ip address 10.1.1.1 255.255.255.252
duplex auto
speed auto
no keepalive
!
interface FastEthernet1/1
ip address 20.1.1.1 255.255.255.252
duplex auto
speed auto
no keepalive
!
router ospf 1
router-id 5.5.5.5
network 5.5.5.5 0.0.0.0 area 0
network 10.1.1.0 0.0.0.3 area 0
network 20.1.1.0 0.0.0.3 area 0
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
no cdp run
!
!
!
control-plane
!
!
!
mgcp profile default
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
stopbits 1
line vty 0 4
login
transport input all
!
!
end
vEOS-2
! Command: show running-config
! device: vEOS-2 (vEOS, EOS-4.16.6M)
!
! boot system flash:/vEOS-lab.swi
!
transceiver qsfp default-mode 4x10G
!
no lldp run
!
hostname vEOS-2
!
spanning-tree mode mstp
!
no aaa root
!
vlan 10
!
interface Ethernet1
no switchport
ip address 20.1.1.2/30
!
interface Ethernet2
switchport access vlan 10
!
interface Ethernet3
!
interface Ethernet4
!
interface Loopback0
ip address 2.2.2.2/32
!
interface Management1
!
interface Vxlan1
vxlan source-interface Loopback0
vxlan udp-port 4789
vxlan vlan 10 vni 4096
vxlan flood vtep 1.1.1.1
!
ip routing
!
router ospf 1
router-id 2.2.2.2
network 2.2.2.2/32 area 0.0.0.0
network 20.1.1.0/30 area 0.0.0.0
max-lsa 12000
!
!
end
후기
- Cisco 장비가 underlay network으로 IP multicast를 사용함으로써 PIM ASM 똫는 PIM Bidir를 장비별로 요구하는데 반해, Unicast IP를 사용함으로써 Deployment의 제약이 적은것 같다.
