Link Aggregation Group and Link AggregationControl Protocol
This chapter describes Link Aggregation Group, Link Aggregation Control Protocol, and manual loadbalancing. This chapter also describes the configuration procedures.
This chapter includes the following topics.
• Understanding IEEE 802.3ad Link Bundling, page 1
• Link Aggregation Group and Link Aggregation Control Protocol Configuration Procedures, page 2
• Understanding LACP, page 2
• Understanding LACP Priority, page 6
• Understanding LACP 1:1 Redundancy, page 8
• Understanding LAG, page 10
• Understanding Load Balancing, page 17
• Show Commands, page 23
• Interactions of LAG with Other Features, page 26
Understanding IEEE 802.3ad Link BundlingThe IEEE 802.3ad link bundling feature provides a method for aggregating multiple Ethernet links into asingle logical channel based on the IEEE 802.3ad standard. This feature helps improve the cost effectivenessof a device by increasing cumulative bandwidth without necessarily requiring hardware upgrades. In addition,the IEEE 802.3ad link bundling feature provides a capability to dynamically provision, manage, and monitorvarious aggregated links and enables interoperability between various Cisco devices and devices of third-partyvendors.
Benefits of Link Bundling
The IEEE 802.3ad link bundling feature provides the following benefits:
• Increased network capacity without changing physical connections or upgrading hardware.
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• Cost savings resulting from use of existing hardware and software for additional functions.
• A standard solution that enables interoperability of network devices.
• Port redundancy without user intervention when an operational port fails.
Link Aggregation Group and Link Aggregation Control ProtocolConfiguration Procedures
To configure Link Aggregation Group (LAG) and Link Aggregation Control Protocol (LACP) using CiscoIOS commands, complete the following procedures:
• Configuring and Retrieving a Port Channel, on page 3
• Configuring LACP over Port Channel, on page 5
• Monitoring LACP Status, on page 6
• Setting LACP System Priority, on page 7
• Configuring LACP 1:1 Redundancy with Fast Switchover, on page 8
• Configuring a Channel Group with LACP, on page 11
• Adding and Removing Interfaces from a Channel Group with LAG, on page 14
• Setting a Minimum and Maximum Threshold of Active Links, on page 16
• Configuring Manual Load Balancing with LAG, on page 21
Understanding LACPThe LACP is part of the IEEE802.3ad standard that enables you to bundle several physical ports together toform a single logical channel. LACP enables a network device, such as a switch, to negotiate an automaticbundling of links by sending LACP packets to the peer device. The LACP is a control protocol over LAG tocheck for any LAG misconfigurations.
LACP enables you to form a single Layer 2 link automatically from two or more Ethernet links. This protocolensures that both ends of the Ethernet link are functional and agree to be members of the aggregation group.LACP must be enabled at both ends of the link to be operational.
For more information on LACP, see the IEEE802.3ad standard document.
LACP Advantages
LACP provides high reliability and redundancy. If a port fails, traffic continues on the remaining ports.
LACP Functions
LACP performs the following functions in the system:
• Maintains configuration information to control aggregation.
• Exchanges configuration information with other peer devices.
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Link Aggregation Group and Link Aggregation Control ProtocolLink Aggregation Group and Link Aggregation Control Protocol Configuration Procedures
• Attaches or detaches ports from the LAG based on the exchanged configuration information.
LACP Modes
LACP can be configured in the following modes:
• Active—In this mode, the ports send LACP packets at regular intervals to the partner ports.
• Passive—In this mode, the ports do not send LACP packets until the partner port sends LACP packets.After receiving the LACP packets from the partner port, the ports send LACP packets to the partnerport.
When you enable LACP on the channel group, LACP exchanges Protocol Data Units (PDU) of size 128bytes. Hence, if the Maximum Transmission Unit (MTU) size of the channel group is set to a value lessthan 128 bytes, the protocol data units are dropped and the channel group interface goes down.
A maximum of 8 member links are supported per port channel. A member link cannot belong to morethan one port channel at the same time.
Note
Managing LACPPerform any of the following procedures as needed:
• Configuring and Retrieving a Port Channel, on page 3
• Configuring LACP over Port Channel, on page 5
• Monitoring LACP Status, on page 6
Configuring and Retrieving a Port Channel
You must manually create a port channel logical interface. Configuring the IP address on the port channelinterface is not supported.
Note
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channel channel-number4. end5. show running-config interface port-channel channel-number6. end
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Link Aggregation Group and Link Aggregation Control ProtocolManaging LACP
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Identifies the interface port channel and entersinterface configuration mode.
interface port-channel channel-number
Example:Switch(config)# interface port-channel 10
Step 3
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 4
Displays the port channel configuration.show running-config interface port-channelchannel-number
Step 5
Example:Switch# show running-config interfaceport-channel 10
Ends the current configuration session.end
Example:Switch# end
Step 6
Example: Verify the Port Channel Configuration
The following example shows how to verify the port channel configuration using Cisco IOS commands.
Switch# show running-config interface port-channel 100
Building configuration...
Current configuration : 139 bytes!interface Port-channel100no ip addresscarrier-delay msec 0l2protocol peer cdp lacpl2protocol forward stp vtp dtp pagp dot1xend
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring and Retrieving a Port Channel
Configuring LACP over Port Channel
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channel channel-number4. exit5. interface type number6. channel-group channel-number mode {active | passive}7. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Identifies the interface port channel and enters interfaceconfiguration mode.
interface port-channel channel-number
Example:Switch(config)# interface port-channel 10
Step 3
Returns to interface configuration mode.exit
Example:Switch(config-if)# exit
Step 4
Specifies the interface to configure and enters interfaceconfiguration mode.
interface type number
Example:Switch(config)# interface TenGigabitEthernet0/45
Step 5
Configures the interface in a channel group and sets thelacp mode.
channel-group channel-numbermode {active | passive}
Example:Switch(config-if)# channel-group 10 mode active
Step 6
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 7
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring LACP over Port Channel
Monitoring LACP StatusFor examples of show lacp commands, see Show Commands, on page 23.
SUMMARY STEPS
1. enable2. show lacp {channel-group-number | counters | internal [detail] | neighbor [detail] | sys-id}3. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Displays LACP information.show lacp {channel-group-number | counters | internal[detail] | neighbor [detail] | sys-id}
Step 2
Example:Switch# show lacp internal
Ends the current configuration session.end
Example:Switch# end
Step 3
Understanding LACP PriorityLACP uses the following parameters to control aggregation:
• LACP system priority—The system priority can be configured automatically or through the CLI. LACPuses the system priority with the deviceMAC address to form the system ID and also during negotiationswith other systems. The range of LACP system priority is from 0 to 65535. The default value is 32768.
• LACP port priority—The port priority can be configured automatically or through the CLI. LACP usesthe port priority to decide which ports must be placed first in aggregation. LACP also uses the portpriority with the port number to form the port identifier. The range of LACP port priority is from 0 to65535. The default value is 32768.
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Link Aggregation Group and Link Aggregation Control ProtocolMonitoring LACP Status
• LACP administrative key—LACP automatically configures an administrative key value on each portconfigured to use LACP. The administrative key defines the ability of a port to aggregate with otherports. The ability of the port to aggregate with the other ports is determined by the following:
◦Port physical characteristics such as data rate, duplex capability, and point-to-point or sharedmedium.
◦Configuration restrictions that you establish.
Setting LACP System Priority
SUMMARY STEPS
1. enable2. configure terminal3. lacp system–priority priority4. end5. show lacp {channel-group-number | counters | internal [detail] | neighbor [detail] | sys-id}6. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Sets the system priority. The range of the LACP systempriority is from 0 to 65535. The default value is 32768.
lacp system–priority priority
Example:Switch(config)# lacp system-priority 200
Step 3
Returns to privileged EXEC mode.end
Example:Switch(config)# end
Step 4
Displays the LACP information.show lacp {channel-group-number | counters | internal[detail] | neighbor [detail] | sys-id}
Step 5
Example:Switch# show lacp sys-id
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Link Aggregation Group and Link Aggregation Control ProtocolSetting LACP System Priority
PurposeCommand or Action
Ends the current configuration session.end
Example:Switch# end
Step 6
Understanding LACP 1:1 RedundancyThe LACP 1:1 redundancy feature provides an EtherChannel configuration with one active link and fastswitchover to a hot standby link.
To use the LACP 1:1 redundancy feature, configure the LACP EtherChannel with two ports (one active andone standby). If the active link goes down, the EtherChannel stays up and the system performs fast switchoverto the hot standby link. When the failed link becomes operational again, the EtherChannel performs anotherfast switchover to revert to the original active link.
For the LACP 1:1 redundancy feature to work correctly, especially the fast switchover capability, the featureneeds to be enabled at both ends of the link.
Configuring LACP 1:1 Redundancy with Fast SwitchoverFor the LACP 1:1 redundancy feature, the channel group must contain two links, of which only one is active.The link with the lower port priority number (and therefore a higher priority) becomes the active link, andthe other link moves to a hot standby state. The maximum number of active member ports (lacpmax–bundle)must be set to 1.
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channel channel-number4. lacp fast-switchover5. lacp max-bundle number6. end7. show running-config interface port-channel channel-number
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
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PurposeCommand or Action
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Identifies the interface port channel and enters interfaceconfiguration mode.
interface port-channel channel-number
Example:Switch(config)# interface port-channel 10
Step 3
Enables the fast switchover feature for this channelgroup.
lacp fast-switchover
Example:Switch(config-if)# lacp fast-switchover
Step 4
Sets the maximum number of active member ports inthe channel group to 1.
lacp max-bundle number
Example:Switch(config-if)# lacp max-bundle 1
Step 5
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 6
Displays the port channel configuration.show running-config interface port-channelchannel-number
Step 7
Example:Switch# show running-config interface port-channel10
Example: Configure LACP 1:1 Redundancy with Fast Switchover
The following example shows how to configure the LACP channel group with 1:1 redundancy using CiscoIOS commands. Because the Ten Gigabit Ethernet port 0/45 is configured with a higher port priority number(and therefore a lower priority) than the default value of 32768, it becomes the standby port.
Switch> enableSwitch# configure terminalSwitch(config)# lacp system-priority 33000Switch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# channel-group 1 mode activeSwitch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# lacp port-priority 33000Switch(config)# interface port-channel 1Switch(config-if)# lacp fast-switchoverSwitch(config-if)# lacp max-bundle 1Switch(config-if)# endSwitch(config)# show run interface port-channel 1
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring LACP 1:1 Redundancy with Fast Switchover
Understanding LAGThe LAG or an EtherChannel, bundles individual Ethernet links into a single logical link that provides theaggregate bandwidth of up to eight physical links. When an Ethernet Flow Point is configured on LAG, theEFP is protected against link failures.
When a link within an EtherChannel fails, the traffic previously carried over the failed link switches to theremaining links within that EtherChannel.
LAG supports manual load balancing and platform default load balancing. LAG supports Ethernet services.
Restrictions for LAG
• All the member links of LAG must be connected to the same Cisco ME 2600X system and must be ofthe same interface type (10GE or 1GE). For example, one member link can be present in one Cisco ME2600X and another member link can be present in another Cisco ME 2600X. These two Cisco ME2600X panels must be connected to the same Cisco ME 2600X system.
• All the member links of LAG must operate at the same link speed and in full-duplex mode. LACP doesnot support the half-duplex mode.
• Member links with varying speed can be added to the same port-channel with LAG.
• If you configure a physical port as part of LAG, you cannot configure Ethernet Virtual Circuits (EVCs)under that physical port.
• Maximum of 8 member links are supported per LAG. A member link cannot belong to more than oneLAG at the same time.
• Maximum number of port channel interfaces supported are 64.
• If you remove a member from a port-channel configured with a low value carrier delay, all other linksin the port-channel flap.
Managing a Channel GroupPerform any of the following procedures as needed:
• Configuring a Channel Group with LACP, on page 11
• Adding and Removing Interfaces from a Channel Group with LAG, on page 14
• Setting a Minimum and Maximum Threshold of Active Links, on page 16
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Configuring a Channel Group with LACP
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channel channel-number4. interface type number5. channel-group channel-number mode {active | passive}6. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Identifies the interface port channel.interface port-channel channel-number
Example:Switch(config)# interface port-channel 5
Step 3
Configures a member interface and enters interfaceconfiguration mode.
interface type number
Example:Switch(config-if)# interface TenGigabitEthernet0/45
Step 4
Configures the channel group with the LACP.channel-group channel-number mode {active | passive}
Example:Switch(config-if)# channel-group 5 mode active
Step 5
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 6
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring a Channel Group with LACP
Example: Configure a Channel Group with LACP
The following example shows how to configure the channel group number 5 using Cisco IOS commands.
Switch> enableSwitch# configure terminalSwitch(config)# interface port-channel 5Switch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# channel-group 5 mode activeSwitch(config-if)# exit
Adding and Removing Interfaces from a Channel Group with LACPPrerequisiteConfiguring and Retrieving a Port Channel, on page 3
SUMMARY STEPS
1. enable2. configure terminal3. interface type number4. channel-group channel-group-number mode {active | passive}5. no channel-group channel-group-number6. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Configures a member interface and enters the interfaceconfiguration mode.
interface type number
Example:Switch(config)# interface TenGigabitEthernet 0/45
Step 3
Adds a Ten Gigabit Ethernet interface to a channelgroup.
channel-group channel-group-number mode {active |passive}
Example:Switch(config-if)# channel-group 5 mode active
Step 4
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Link Aggregation Group and Link Aggregation Control ProtocolAdding and Removing Interfaces from a Channel Group with LACP
PurposeCommand or Action
Removes the Ten Gigabit Ethernet interface from thechannel group.
no channel-group channel-group-number
Example:Switch(config-if)# no channel-group 5
Step 5
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 6
Example: Add and Remove Interface from a Channel Group
The following example shows how to add an interface to a channel group using Cisco IOS commands:
Switch> enableSwitch# configure terminalSwitch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# channel-group 5 mode activeSwitch(config-if)# exit
The following example shows how to remove an interface from a channel group using Cisco IOS commands:
Switch> enableSwitch# configure terminalSwitch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# no channel-group 5Switch(config-if)# exit
Configuring a Channel Group with LAG
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channel channel-number4. interface type number5. channel-group channel-number6. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring a Channel Group with LAG
PurposeCommand or Action
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Identifies the interface port channel.interface port-channel channel-number
Example:Switch(config)# interface port-channel 5
Step 3
Configures a member interface and enters interfaceconfiguration mode.
interface type number
Example:Switch(config)# interface TenGigabitEthernet 0/45
Step 4
Configures the channel group with the LACP.channel-group channel-number
Example:Switch(config-if)# channel-group 5
Step 5
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 6
Example: Configure a Channel Group with LAG
The following example shows how to configure the channel group number 5 using Cisco IOS commands.
Switch> enableSwitch# configure terminalSwitch(config)# interface port-channel 5Switch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# channel-group 5Switch(config-if)# exit
Adding and Removing Interfaces from a Channel Group with LAGPrerequisiteConfiguring and Retrieving a Port Channel, on page 3
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Link Aggregation Group and Link Aggregation Control ProtocolAdding and Removing Interfaces from a Channel Group with LAG
SUMMARY STEPS
1. enable2. configure terminal3. interface type number4. channel-group channel-group-number5. no channel-group channel-group-number6. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Configures a member interface and enters the interfaceconfiguration mode.
interface type number
Example:Switch(config)# interface TenGigabitEthernet0/45
Step 3
Adds a Ten Gigabit Ethernet interface to a channelgroup.
channel-group channel-group-number
Example:Switch(config-if)# channel-group 5
Step 4
Removes the Ten Gigabit Ethernet interface from thechannel group.
no channel-group channel-group-number
Example:Switch(config-if)# no channel-group 5
Step 5
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 6
Example: Add and Remove Interface from a Channel Group
The following example shows how to add an interface to a channel group using Cisco IOS commands:
Switch> enableSwitch# configure terminalSwitch(config)# interface TenGigabitEthernet 0/45
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Link Aggregation Group and Link Aggregation Control ProtocolAdding and Removing Interfaces from a Channel Group with LAG
Switch(config-if)# channel-group 5Switch(config-if)# exit
The following example shows how to remove an interface from a channel group using Cisco IOS commands:
Switch> enableSwitch# configure terminalSwitch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# no channel-group 5Switch(config-if)# exit
Setting a Minimum and Maximum Threshold of Active Links
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channel channel-number4. lacp min-bundle min-bundle-number5. lacp max-bundle max-bundle-number6. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Creates a port channel virtual interface and enters interfaceconfiguration mode.
interface port-channel channel-number
Example:Switch(config)# interface port-channel 1
Step 3
Sets the minimum threshold of active member links allowedin the LACP bundle. The range is 1 to 8.
lacp min-bundle min-bundle-number
Example:Switch(config-if)# lacp min-bundle 5
Step 4
Sets the maximum threshold of active member links allowedin the LACP bundle. The range is 1 to 8. The maximum
lacp max-bundle max-bundle-number
Example:Switch(config-if)# lacp max-bundle 7
Step 5
threshold value must be greater than or equal to the minimumthreshold value.
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Link Aggregation Group and Link Aggregation Control ProtocolSetting a Minimum and Maximum Threshold of Active Links
PurposeCommand or Action
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 6
Example: Set a Minimum Threshold of Active Links
The following example shows how to set a minimum threshold of active member links using Cisco IOScommands:
Switch> enableSwitch# configure terminalSwitch(config)# interface port-channel 1Switch(config-if)# lacp min-bundle 5Switch(config-if)# end
Understanding Load BalancingManual load balancing enables you to manually specify which member link a service instance must use forits egress traffic. This allows you, who has knowledge about the type of traffic traversing an EFP, to equallydistribute EFPs.
The ingress traffic for any EFP can arrive on any member link of the LAG. All the egress traffic for theEFP must use only one of the member links.
Note
EFPs can be configured on a channel group. The traffic, carried by the EFPs, is load balanced across themember links. Ingress traffic for a single EVC can arrive on any member of the bundle. All egress traffic foran EFP uses only one of the member links. The load balancing is achieved by distributing EFPs between themember links. The EFPs on a channel group are grouped and each group is associated with a member link.The manual load balancing mechanism can be used to control the EFP grouping.
Cisco ME 2600X supports manual load balancing and platform default load balancing. Cisco ME 2600Xdoes not support weighted load balancing in this release. When manual load balancing is not configuredand applied to the service instance, the default platform load balancing mechanism is used.
Note
Default Load Balancing
In the default load balancing mechanism, the EFP traffic is distributed based on a hashing algorithm that isdetermined by the service instance ID and the number of active members in the channel group. The defaultload balancing algorithm is explained below.
(Service-instance ID) ÷ max_num_links
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Link Aggregation Group and Link Aggregation Control ProtocolUnderstanding Load Balancing
The maximum number of member links (max_num_links) supported in Cisco ME 2600X is 8. Hence,(Service-instance ID) ÷max_num_links value provides a hash bit value from 0 to 7. This value is then comparedwith the load share of each member link.
The load share is allocated for each active member link based on the number of active member links in thechannel group. The member link whose load share contains the hash bit is selected as the egress link.
The load share derivation is as follows:
The default load share allocation algorithm allocates the load share bits sequentially to the member links.
Let us consider that we have 4 active links as follows. The load share calculation varies based on the link idsdefined.
Member-1:4/1- 0 0 0 1 0 0 0 1 = 0x11
Member-2:4/2- 0 0 1 0 0 0 1 0 = 0x22
Member-3:4/3- 0 1 0 0 0 1 0 0 = 0x44
Member-4:4/4- 1 0 0 0 1 0 0 0 = 0x88
Configuring Load Balancing
1 Create a channel group and add 4 member links (4/1, 4/2, 4/3, and 4/4).
2 The load share is calculated for the active member links.
3 Create a service with ID10 on the channel group.
4 On applying the algorithm: (Service-instance ID) ÷ max_num_links, we get 10 ÷ 8 == 2 (hash bit).
5 In the loadshare derived above, the hash bit = 2 is set for the port 4/3 and hence 4/3 is chosen as the egressport for the service 10.
6 The same procedure is repeated when services are added to obtain the egress port.
Configuring Manual Load Balancing with LACPPrerequisiteConfiguring a Channel Group with LACP, on page 11
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring Manual Load Balancing with LACP
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channelchannel-number4. service instance id ethernet5. encapsulation untagged, dot1q {any | vlan-id} second-dot1q {any | vlan-id}6. bridge-domain bridge-id7. exit8. port-channel load-balance {link link-id}9. backup link link-id10. service-instance id11. exit12. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:
Step 2
RSwitch# configure terminal
Creates a port channel virtual interface and enters interfaceconfiguration mode.
interface port-channelchannel-number
Example:Switch(config)# interface port-channel 10
Step 3
Configures an Ethernet service instance on an interfaceand enters service instance configuration mode.
service instance id ethernet
Example:Switch(config-if)# service instance 100ethernet
Step 4
Defines the matching criteria that maps the ingress dot1q,QinQ, or untagged frames on an interface to theappropriate service instance.
encapsulation untagged, dot1q {any | vlan-id}second-dot1q {any | vlan-id}
Example:Switch(config-if-srv)# encapsulation dot1q 100
Step 5
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PurposeCommand or Action
Binds the Ethernet service instance to a bridge domaininstance where bridge-id is the identifier for the bridgedomain instance.
bridge-domain bridge-id
Example:Switch(config-if-srv)# bridge-domain 100
Step 6
Exits the service instance configuration mode.exit
Example:Switch(config-if-srv)# exit
Step 7
Configures the primary load balanced link.port-channel load-balance {link link-id}
Example:Switch(config-if)# port-channel load-balancelink 1
Step 8
Configures the back up links under the primary link.backup link link-id
Example:Switch(config-if-lb)# backup link 2,3,4
Step 9
Assigns a service instance to a member link for manualload balancing
service-instance id
Example:Switch(config-if-lb)# service-instance 100
Step 10
Returns to interface configuration mode.exit
Example:Switch(config-if-lb)# exit
Step 11
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 12
Example: Configuring Manual Load Balancing with LACP
The following example shows how the service instances 100 and 101 are manually assigned to link 1 on TenGigabit Ethernet interface 0/45. The service instances are also assigned backup links 2, 3, and 4.
Switch# configure terminalSwitch(config)# interface port-channel 10Switch(config-if)# service instance 100 ethernetSwitch(config-if-srv)# encapsulation dot1q 100Switch(config-if-srv)# bridge-domain 100Switch(config-if-srv)# exitSwitch(config-if)# service instance 101 ethernetSwitch(config-if-srv)# encapsulation dot1q 101Switch(config-if-srv)# bridge-domain 101Switch(config-if-srv)# exitSwitch(config-if)# port-channel load-balance link 1Switch(config-if-lb)# backup link 2,3,4Switch(config-if-lb)# service-instance 100,101
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring Manual Load Balancing with LACP
Switch(config-if-lb)# exit
Switch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# channel-group 10 mode active link 1Switch(config-if)# exit
Configuring Manual Load Balancing with LAGPrerequisiteConfiguring a Channel Group with LAG, on page 13
SUMMARY STEPS
1. enable2. configure terminal3. interface port-channelchannel-number4. service instance id ethernet5. encapsulation untagged, dot1q {any | vlan-id} second-dot1q {any | vlan-id}6. bridge-domain bridge-id7. exit8. port-channel load-balance {link link-id}9. backup link link-id10. service-instance id11. exit12. end
DETAILED STEPS
PurposeCommand or Action
Enables privileged EXEC mode.enableStep 1
Example:Switch> enable
• Enter your password if prompted.
Enters global configuration mode.configure terminal
Example:Switch# configure terminal
Step 2
Creates a port channel virtual interface and enters interfaceconfiguration mode.
interface port-channelchannel-number
Example:Switch(config)# interface port-channel 10
Step 3
Configures an Ethernet service instance on an interfaceand enters service instance configuration mode.
service instance id ethernet
Example:Switch(config-if)# service instance 100ethernet
Step 4
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PurposeCommand or Action
Defines the matching criteria that maps the ingress dot1q,QinQ, or untagged frames on an interface to theappropriate service instance.
encapsulation untagged, dot1q {any | vlan-id}second-dot1q {any | vlan-id}
Example:Switch(config-if-srv)# encapsulation dot1q 100
Step 5
Binds the Ethernet service instance to a bridge domaininstance where bridge-id is the identifier for the bridgedomain instance.
bridge-domain bridge-id
Example:Switch(config-if-srv)# bridge-domain 100
Step 6
Exits the service instance configuration mode.exit
Example:Switch(config-if-srv)# exit
Step 7
Configures the primary load balanced link.port-channel load-balance {link link-id}
Example:Switch(config-if)# port-channel load-balancelink 1
Step 8
Configures the back up links under the primary link.backup link link-id
Example:Switch(config-if-lb)# backup link 2,3,4
Step 9
Assigns a service instance to a member link for manualload balancing
service-instance id
Example:Switch(config-if-lb)# service-instance 100
Step 10
Returns to interface configuration mode.exit
Example:Switch(config-if-lb)# exit
Step 11
Returns to privileged EXEC mode.end
Example:Switch(config-if)# end
Step 12
Example: Configuring Manual Load Balancing with LAG
The following example shows how the service instances 100 and 101 are manually assigned to link 1 on TenGigabit Ethernet interface 0/45. The service instances are also assigned backup links 2, 3, and 4.
Switch# configure terminalSwitch(config)# interface port-channel 10Switch(config-if)# service instance 100 ethernetSwitch(config-if-srv)# encapsulation dot1q 100Switch(config-if-srv)# bridge-domain 100Switch(config-if-srv)# exit
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Link Aggregation Group and Link Aggregation Control ProtocolConfiguring Manual Load Balancing with LAG
Switch(config-if)# service instance 101 ethernetSwitch(config-if-srv)# encapsulation dot1q 101Switch(config-if-srv)# bridge-domain 101Switch(config-if-srv)# exitSwitch(config-if)# port-channel load-balance link 1Switch(config-if-lb)# backup link 2,3,4Switch(config-if-lb)# service-instance 100,101Switch(config-if-lb)# exit
Switch(config)# interface TenGigabitEthernet 0/45Switch(config-if)# channel-group 10 mode link 1Switch(config-if)# exit
Show CommandsDisplay Port Channel Statistics
The following example shows how to view port channel statistics.
Switch# show interfaces stats
GigabitEthernet 0/1Switching path Pkts In Chars In Pkts Out Chars OutProcessor 108470 31042570 82259 14255449Route cache 0 0 0 0Total 108470 31042570 82259 14255449GigabitEthernet 0/2Switching path Pkts In Chars In Pkts Out Chars OutProcessor 15979 19073260 15192 1325713Route cache 0 0 0 0Total 15979 19073260 15192 1325713Port-channel15Switching path Pkts In Chars In Pkts Out Chars OutProcessor 0 0 0 0Route cache 0 0 0 0Total 0 0 0 0
Switch# show interfaces port-channel 2 stats
Port-channel2Switching path Pkts In Chars In Pkts Out Chars Out
Processor 570546645 295127854241 557694541 291427545417Route cache 0 0 0 0
Total 570546645 295127854241 557694541 291427545417
Display Port Channel Interface
The following example shows how to view the information for a port channel interface. channel-id is aninteger value between 1 to 64.
Switch# show interfaces port-channel channel-id
Switch# show interfaces port-channel 20
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Link Aggregation Group and Link Aggregation Control ProtocolShow Commands
Port-channel20 is up, line protocol is upHardware is GEChannel, address is 0002.0415.0002 (bia 0000.0000.0000)MTU 9600 bytes, BW 10000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255Encapsulation ARPA, loopback not setKeepalive set (10 sec)ARP type: ARPA, ARP Timeout 04:00:00No. of active members in this channel: 1
Member 0 : TenGigabitEthernet 0/45 , Full-duplex, 10000Mb/sNo. of passive members in this channel: 0
Last input never, output never, output hang neverLast clearing of "show interface" counters neverInput queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0Queueing strategy: fifoOutput queue: 0/40 (size/max)5 minute input rate 0 bits/sec, 0 packets/sec5 minute output rate 0 bits/sec, 0 packets/sec
37 packets input, 7820 bytes, 0 no bufferReceived 0 broadcasts (0 IP multicasts)0 runts, 0 giants, 0 throttles0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored0 watchdog, 0 multicast, 0 pause input39 packets output, 8088 bytes, 0 underruns0 output errors, 0 collisions, 0 interface resets0 unknown protocol drops0 babbles, 0 late collision, 0 deferred0 lost carrier, 0 no carrier, 0 pause output0 output buffer failures, 0 output buffers swapped out
Display EFP Statistics
The following example shows how to view EFP statistics.
Switch> show ethernet service instance stats
System maximum number of service instances: 32768Service Instance 2, Interface TenGigabitEthernet 0/45Pkts In Bytes In Pkts Out Bytes Out
0 0 0 0Service Instance 2, Interface Port-channel15Pkts In Bytes In Pkts Out Bytes Out
0 0 0 0
Display LACP Activity
The following examples show how to view LACP activity in the network.
Switch# show lacp internal
Flags: S - Device is requesting Slow LACPDUsF - Device is requesting Fast LACPDUsA - Device is in Active mode P - Device is in Passive mode
Channel group 20
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Link Aggregation Group and Link Aggregation Control ProtocolShow Commands
LACP port Admin Oper Port PortPort Flags State Priority Key Key Number StateTe4/2 SA bndl 32768 0x5 0x5 0x42 0x3D
Switch# show lacp 20 counters
LACPDUs Marker Marker Response LACPDUsPort Sent Recv Sent Recv Sent Recv Pkts Err
---------------------------------------------------------------------Channel group 20Te4/2 21 18 0 0 0 0 0
Switch# show lacp 20 internal
Flags: S - Device is requesting Slow LACPDUsF - Device is requesting Fast LACPDUsA - Device is in Active mode P - Device is in Passive mode
Channel group 20LACP port Admin Oper Port Port
Port Flags State Priority Key Key Number StateTe4/2 SA bndl 32768 0x5 0x5 0x42 0x3D
Switch# show lacp 20 neighbor
Flags: S - Device is requesting Slow LACPDUsF - Device is requesting Fast LACPDUsA - Device is in Active mode P - Device is in Passive mode
Channel group 20 neighbors
Partner's information:
Partner Partner LACP Partner Partner Partner Partner PartnerPort Flags State Port Priority Admin Key Oper Key Port Number PortState
Te4/2 SA 32768 0011.2026.7300 11s 0x1 0x14 0x3C
Switch# show lacp 20 counters
LACPDUs Marker Marker Response LACPDUsPort Sent Recv Sent Recv Sent Recv Pkts Err-------------------------------------------------------------------------------Channel group: 20Te4/2 26 31 0 0 0 0 0
Switch# show lacp sys-id
32768,0005.9b2e.18e0
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Display Manual Load Balancing Configuration
Switch# show ethernet service instance load-balance
Manually Assigned Load-Balancing Status for Port-channel1
Link ID 1: TenGigabitEthernet 0/45 (Active)Backup: Link ID 2 TenGigabitEthernet 0/45Service instances: 10
Link ID 2: TenGigabitEthernet 0/46 (Active)Backup: Link ID 1 TenGigabitEthernet 0/46Service instances: 20
Switch# show ethernet service instance platform
Displays the port channel EFPs that are currently using the manual or platform load balancing and the egresslink.
EFP id: 10 Interface Port-channel1Load balancing type: ManualAssociated Egress Interface: TenGigabitEthernet 0/45
EFP id: 20 Interface Port-channel1Load balancing type: ManualAssociated Egress Interface: TenGigabitEthernet 0/46
EFP id: 10 Interface Port-channel2Load balancing type: ManualAssociated Egress Interface: TenGigabitEthernet 0/47
EFP id: 20 Interface Port-channel2Load balancing type: PlatformAssociated Egress Interface: TenGigabitEthernet 0/48
Interactions of LAG with Other FeaturesLAG interacts with the following features:
• EVC
• QoS
• IGMP Snooping
LAG with EVC
EFPs can be configured on a channel group. The traffic, carried by the EFPs, is load balanced across themember links. Ingress traffic for a single EVC can arrive on any member of the bundle. All egress traffic foran EFP uses only one of the member links. The load balancing is achieved by distributing EFPs between themember links. The EFPs on a channel group are grouped and each group is associated with a member link.In the default load balancing mechanism, there is no control over how the EFPs are distributed together, andsometimes the EFP distribution is not ideal. The manual load balancing mechanism can be alternatively usedto control the EFP grouping.
When you configure a physical port as part of a channel group, you cannot configure EVCs under that physicalport.
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Link Aggregation Group and Link Aggregation Control ProtocolInteractions of LAG with Other Features
LAG can be configured for both point–to–point and point–to–multipoint bridge domains.
The system will support a maximum of 256 EFPs on all the configured port channels.Note
LAG with QoS
See QoS Support on Port-Channel.
LAG with IGMP Snooping
See IGMP Snooping Interaction with LAG.
LAG with REP
REP is not supported on member links that are part of a channel group.
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