Interface Configuration

Module 3B - Port-channel

3B-2

Objectives Identify FTOS Link

Aggregation Groups (aka Port-Channels)

Configure Static Port-Channel

Configure Dynamic Port-Channel with LACP

3B-3

Interface Types

Interface Type Modes

Possible Default Mode

Require Creation

Default State

Physical 1-Gigabit Ethernet, 10-Gigabit Ethernet

interfaces, and SONET interfaces L2, L3 Unset No

Shutdown (disabled)

Management Located on the RPM and provides

management access N/A N/A No

Shutdown (disabled)

Loopback Virtual interface in which the software

emulates a physical interface L3 L3 Yes

No Shutdown (enabled)

Null Virtual interface that is always up, but no

traffic flows on this interface N/A N/A No Enabled

Port Channel Virtual interface that provides redundancy

by allowing the aggregation of up to 16 physical interfaces

L2, L3 Unset Yes Shutdown (disabled)

VLAN Logical interfaces to separate broadcast

domains L2, L3 L2

Yes (except Default)

Shutdown (L2 Forwarding enabled L3 Forwarding disabled)

3B-4

A Port Channel Interface is a Link Aggregation Group (LAG)

Allows aggregation of multiple ports into 1 logical interface Defined in IEEE 802.3ad

Behaves essentially as 1 physical interface and can

Operate in L2 or L3 mode Enable or configure protocols

Assign access control lists

2 Configuration Methods Static (manually)

Dynamic using Link Aggregation Control Protocol (LACP)

A physical interface can belong to only one port-channel

Must be like interface speeds Can be on different line cards

Only those that match the speed of the 1st interface that is physically brought up will be enabled

Port-Channel is UP if at least one member link is up User configured minimum # of

links

3B-5

Up to 255 Port Channels per System

With ExaScale, the maximum # of members that can be added to the LAG = 64

Restriction is the size of the LAG table in ExaScale (2k)

Total number of members in all the LAGs should not exceed a product of 2048

Platform Max. Port-Channels Max. Members per Port-Channel

E-Series Exascale* 64

255

32

8

E-Series Terascale 255 16

Z-Series 128 8

C-Series 128 8

S-Series 52 8

3B-6

Steps to Configure a STATIC Port Channel Interface

1. Create a port-channel interface Force10(conf)# interface port-channel {channel-number}

Force10(conf-if-po-14)# no shutdown

2. Add a physical interface Force10(conf-if-po-14)# channel-member {interface}

Force10(conf-if-po-14)# show config

3. Enable physical interface (no shutdown)

4. View the port channels status and channel members Force10# show interfaces port-channel brief

5. Configure the port channel using commands similar to those found in physical interfaces

3B-7

Delete a Port Channel Force10(conf)# no interface port-channel channel-number

Disable a Port Channel Force10(conf)# shutdown

Configure Minimum Links Port-channel is only considered Up if a minimum number of its channel-

member links are up Force10(conf-if)# minimum-links number

Force10#conf

Force10(conf)#int port-channel 1

Force10(conf-if-po-1)#minimum-links 3

Force10(conf-if-po-1)#

Other Port-channel Commands

3B-8

Link Aggregation Control Protocol (LACP) IEEE 802.1AX

Standardized means of automatically establishing Link Aggregation Groups between the two partner systems

Works by constantly exchanging custom MAC PDUs across LAN Ethernet links

2 Modes of Operation Active ports will generate LACP protocol messages regardless of

whether or not the partner asked to hear them Passive ports will generally not speak unless spoken to

Will not generate LACP messages unless its partner is in Active mode

Off Mode Off mode disables LACP on a given interface

3B-9

1

2

3

1. Enable Physical Interface (GigabitEthernet 3/15)

2. Enable LACP Protocol

3. Assign interface to Port- Channel 32 and set LACP mode to active

4. Repeat steps 1-3 above with additional interfaces

5. Enter CONF mode for Port Channel #32

6. Enable Port Channel Interface

7. Set Port Channel to L2 Mode (optional)

Steps to Configure A DYNAMIC Port Channel Interface (LACP)

Force10(conf)# interface Gigabitethernet 3/15

Force10(conf-if-gi-3/15)#no shutdown

Force10(conf-if-gi-3/15)#port-channel-protocol LACP

Force10(conf-if-gi-3/15)#port-channel 32 mode

active

Force10(conf-if-gi-3/15)#exit

Force10(conf)#interface Gigabitethernet 3/16

Force10(conf-if-gi-3/16)#no shutdown

Force10(conf-if-gi-3/16)#port-channel-protocol LACP

Force10(conf-if-gi-3/16)#port-channel 32 mode

active

Force10(conf-if-gi-3/16)#exit

Force10(conf)#interface port-channel 32

Force10(conf-if-po-32)#no shutdown

Force10(conf-if-po-32)#switchport

4

5

6

7

3B-10

Port-Channel/LAG Load Balancing

On the E-Series, the default load-balance criteria is based on a 5-tuple, as follows: IP source address

IP destination address Protocol type

TCP/UDP source port TCP/UDP destination port

To change LAG load balancing algorithm: Force10(conf)# [no] load-balance [ip-selection {3-tuple | packet-based}] [mac]

3B-11

Comparing Static vs. LACP Port-Channels

STATIC Port-Channel Configure within the Port-

channel

DYNAMIC Port-Channel Configure within the interface

R3#show run int port-channel 10

! interface Port-channel 10 no ip address

switchport channel-member GigabitEthernet

3/15-16 no shutdown

R3#show run interface gig 3/15

! interface GigabitEthernet 3/15 no ip address no shutdown

R3#

R3#show run int port-channel 10

! interface Port-channel 10 no ip address

switchport no shutdown

R3#show run interface gig 3/15

! interface GigabitEthernet 3/15 no ip address port-channel-protocol LACP port-channel 10 mode active no shutdown

T_R3#

3B-12

Summary In this module we covered:

FTOS Link Aggregation Groups

(aka Port-Channels)

Static Port-Channel Configuration

Dynamic Port-Channel Configuration with LACP