Link Aggregation

V1.1

Objectives

Understand the features and benefits of link aggregation

Grasp the basic link aggregation configuration steps of G series

Agenda

Features and benefits of link aggregation G series link aggregation configuration

What is Link aggregation?

Link aggregation introduces a bandwidth aggregation capability

Link aggregation inter-operates seamlessly with network platforms from other vendors such as the Cisco Catalyst 5000 and server vendors such as SUN Microsystems and Auspex.

Link aggregation is the ability to aggregate 10/100 or Gigabit Ethernet links between devices and operate the group of links as a single high capacity link.

Port trunking Fast Ethernet 4

Fast Ethernet 3

Fast Ethernet 2

Fast Ethernet 1

D

E

F

A

B

C

Port trunking

Port Trunking

Benefits

Bandwidth is increased by grouping links together. If link D becomes broken, then all the traffic will be redistributed between links A, B, and C automatically.

ABCD

Load Balancing (per flow)

Flows are assigned to a particular link by the load balancing algorithm. The Flow uses the same link throughout its duration. Round-robin (Default setting) Link Utilization

Flow 1 AFlow 2 BFlow 3 CFlow 4 D

D

E

F

D

D

FE 1FE 2FE 3FE …

A->DB->DC->Detc.

Flow Output Path

FE 4FE 3FE 1FE …

D->AD->BD->Cetc.

Flow Output Path

D D D D DDA

B

C

D

Fast Ethernet 4

Fast Ethernet 3

Fast Ethernet 2

Fast Ethernet 1

Port trunking Port trunking

Load Balance

Port trunking uses load distribution to share the links

Agenda

Features and benefits of link aggregation G series link aggregation configuration

Configuration of G Series

The G series equipment supports up to 32 TRUNK groups; one TRUNK group contains 8 ports at most.

The G series equipment supports the aggregation of ports from different slots, but all ports should be under the same duplex mode and have the same speed.

The G series equipment supports three modes of ports:access, trunk or hybrid， but all ports in one group should be same.

Three preconditions of link aggregation

Support link aggregation across interface cards, member port can be at any interface card, but the member port must work at full-duplex mode and the working rate must be the same for all the member ports.

Mode of the member ports should be the same, the mode can be access、 trunk or hybrid.

Link aggregation methods

Static trunk Static Trunk add physical ports to the Trunk group to

form a logical port. This way is not good for observing the status of the aggregated port.

LACP (Link aggregation Control Protocol) 1. Comply with IEEE 802.3ad standard.

2. LACP work by protocols to aggregate multiple physical ports to a trunk group, thus forming a logical port dynamically. LACP will automatically aggregate together to get the maximum bandwidth.

Configuration of G Series

1.Create Trunk Group ZXR10(config)#interface <smartgroup-name>

2.Bundling port to trunk group, setting port aggregation modesmartgroup <smartgroup-id> mode {passive|active|on}

When the aggregation mode is set to be On, the port runs static trunk, two ends participating in aggregation should be set to be On mode.

When aggregation mode is active or passive, the port runs LACP. Active means the port is in active negotiation mode; passive means the port is in passive negotiation mode. When configuring dynamic link aggregation, set the aggregation mode of one end port to be active and the other end to be passive, or active both.

Configuration of G Series

3. Setting load balance modesmartgroup load-balance <mode>

ZXR10 T160G/T64G port link aggregation supports 6 types of load balance modes which respectively based on :

dst-ip Dst ip address dst-mac Dst mac address src-dst-ip Src-dst ip address src-dst-mac Src-dst mac address src-ip Src ip address src-mac Src mac adddress

Configuration of G Series

Display the aggregation status of member port: ZXR10(config)#show lacp 2 internal

Smartgroup:2Actor Agg LACPDUs Port Oper Port RX MuxPort State Interval Priority Key State Machine Machine------------------------------------------------------------------fei_3/17 selected 30 32768 0x202 0x3d current collecting-distributingfei_3/18 selected 30 32768 0x202 0x3d current collecting-distributing

Instance of configuration

smartgroup1ZTE1ZTE2

ZTE1(config)# interface smartgroup1

ZTE1(config-if)# exit

ZTE1(config)# interface fei_2/1

ZTE1(config-if)# smartgroup 1 mode on

ZTE1(config-if)# exit

ZTE1(config)# interface fei_2/2

ZTE1(config-if)# smartgroup 1 mode on

ZTE1(config-if)# exit

ZTE1(config)# interface smartgroup1

ZTE1(config-if)# switchport mode trunk

ZTE1(config-if)# switchport trunk vlan 10

Summarization

Link aggregation is used for load balancing

Link aggregation can be used in multi-vendor products environment

The aggregation ports should be under the same duplex mode and have the same speed.

Questions

When to use the link aggregation?

What’s the main feature of link aggregation?

What parameters should be matched in order to add ports to a trunk group?