Etherchannel over L2VPN
Etherchannel over L2VPN
Etherchannel is a link aggregation technology. It allows grouping of several physical Ethernet links to create one logical link. Up to 8 links can be aggregated to form a Port-channel logical interface. Spanning-tree (STP) blocks redundant links, Etherchannel allows load-balancing across those links.
Some guidelines to creating a port-channel-
- Interfaces in the channel do not have to be physically next to each other
- All bundle interfaces must have same speed and duplex settings
- All bundle interfaces must be assigned to same VLAN or all interfaces must be trunks. If they are all trunks, they must be carrying same VLANs and same encapsulation mode
Network topology:
A Layer-2 Etherchannel is setup between SW1 and SW2 customer switches.
Etherchannel configuration on switches
interface Port-channel1
switchport mode trunk
!
interface FastEthernet1/0
switchport mode trunk
channel-group 1 mode on
!
interface FastEthernet1/1
switchport mode trunk
channel-group 1 mode on
!
interface FastEthernet1/2
switchport access vlan 10
!
There are two options to terminate the Etherchannel originating from customer switches-
- to terminate the Etherchannel on PE routers. Then apply the xconnect on the port-channel interface on the PE.
- Apply the xconnect on the physical interfaces itself- one Pseudowire per link which allows end-to-end Etherchannel
This configuration will use option-2.
PW configuration on PE
PE1 router:
interface Loopback 0
ip address 1.1.1.1 255.255.255.255
!
interface fastethernet 1/0
xconnect 2.2.2.2 100 encapsulation mpls
!
interface fastethernet 1/1
xconnect 2.2.2.2 200 encapsulation mpls
!
PE2 router:
interface Loopback 0
ip address 2.2.2.2 255.255.255.255
!
interface fastethernet 1/0
xconnect 1.1.1.1 100 encapsulation mpls
!
interface fastethernet 1/1
xconnect 1.1.1.1 200 encapsulation mpls
!
Verification:
The show etherchannel summary command shows the status of the Etherchannel and the interfaces assigned to the port-channel.
Etherchannel status
SW1# show etherchannel 1 port-channel
Port-channels in the group:
----------------------
Port-channel: Po1
------------
Age of the Port-channel = 00d:00h:49m:05s
Logical slot/port = 8/0 Number of ports = 2
GC = 0x00010001 HotStandBy port = null
Port state = Port-channel Ag-Inuse
Ports in the Port-channel:
Index Port EC state
------+------+------------
1 Fa1/0 on
0 Fa1/1 on
Time since last port bundled: 00d:00h:45m:45s Fa1/0
SW1# show etherchannel 1 summary
Flags: D - down P - in port-channel
I - stand-alone s - suspended
R - Layer3 S - Layer2
U - in use
Group Port-channel Ports
-----+------------+-----------------------------------------------------------
1 Po1(SU) Fa1/0(P) Fa1/1(P)
SW1# show etherchannel 1 detail
Group state = L2
Ports: 2 Maxports = 8
Port-channels: 1 Max Port-channels = 1
Ports in the group:
-------------------
Port: Fa1/0
------------
Port state = Up Mstr In-Bndl
Channel group = 1 Mode = On/FEC Gcchange = 0
Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
Port index = 1
Age of the port in the current state: 00d:00h:47m:02s
Port: Fa1/1
------------
Port state = Up Mstr In-Bndl
Channel group = 1 Mode = On/FEC Gcchange = 0
Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
Port index = 0
Age of the port in the current state: 00d:00h:47m:08s
Port-channels in the group:
----------------------
Port-channel: Po1
------------
Age of the Port-channel = 00d:00h:50m:25s
Logical slot/port = 8/0 Number of ports = 2
GC = 0x00010001 HotStandBy port = null
Port state = Port-channel Ag-Inuse
Ports in the Port-channel:
Index Port EC state
------+------+------------
1 Fa1/0 on
0 Fa1/1 on
Time since last port bundled: 00d:00h:47m:05s Fa1/0
The show mpls l2transport vc detail command shows details of Pseudowires.
PW status
PE1# show mpls l2transport vc
Local intf Local circuit Dest address VC ID Status
------------- -------------------------- --------------- ---------- ----------
Fa1/0 Ethernet 2.2.2.2 100 UP
Fa1/1 Ethernet 2.2.2.2 200 UP
PE1# show mpls l2transport vc detail
Local interface: Fa1/0 up, line protocol up, Ethernet up
Destination address: 2.2.2.2, VC ID: 100, VC status: up
Output interface: Fa0/0, imposed label stack {17 19}
Preferred path: not configured
Default path: active
Next hop: 172.16.1.2
Create time: 00:46:46, last status change time: 00:38:38
Signaling protocol: LDP, peer 2.2.2.2:0 up
Targeted Hello: 1.1.1.1(LDP Id) -> 2.2.2.2, LDP is UP
Status TLV support (local/remote) : enabled/supported
LDP route watch : enabled
Label/status state machine : established, LruRru
Last local dataplane status rcvd: No fault
Last local SSS circuit status rcvd: No fault
Last local SSS circuit status sent: No fault
Last local LDP TLV status sent: No fault
Last remote LDP TLV status rcvd: No fault
Last remote LDP ADJ status rcvd: No fault
MPLS VC labels: local 17, remote 19
Group ID: local 0, remote 0
MTU: local 1500, remote 1500
Remote interface description:
Sequencing: receive disabled, send disabled
Control Word: On (configured: autosense)
VC statistics:
transit packet totals: receive 181, send 53
transit byte totals: receive 22944, send 16423
transit packet drops: receive 0, seq error 0, send 0
Local interface: Fa1/1 up, line protocol up, Ethernet up
Destination address: 2.2.2.2, VC ID: 200, VC status: up
Output interface: Fa0/0, imposed label stack {17 18}
Preferred path: not configured
Default path: active
Next hop: 172.16.1.2
Create time: 00:46:45, last status change time: 00:38:38
Signaling protocol: LDP, peer 2.2.2.2:0 up
Targeted Hello: 1.1.1.1(LDP Id) -> 2.2.2.2, LDP is UP
Status TLV support (local/remote) : enabled/supported
LDP route watch : enabled
Label/status state machine : established, LruRru
Last local dataplane status rcvd: No fault
Last local SSS circuit status rcvd: No fault
Last local SSS circuit status sent: No fault
Last local LDP TLV status sent: No fault
Last remote LDP TLV status rcvd: No fault
Last remote LDP ADJ status rcvd: No fault
MPLS VC labels: local 18, remote 18
Group ID: local 0, remote 0
MTU: local 1500, remote 1500
Remote interface description:
Sequencing: receive disabled, send disabled
Control Word: On (configured: autosense)
VC statistics:
transit packet totals: receive 120, send 3684
transit byte totals: receive 19260, send 342952
transit packet drops: receive 0, seq error 0, send 0