Dynamic-LAG Minimum Link Configuration
Configure the minimum number of ports that must be linked up and bundled in the LACP port channel. We can configure the minimum links range from 2 to 32. If the number of ports aggregated to the port channel is less than the minimum number of links configured, then the port channel enters the Protocol Down because of the minimum link state.
Note: Minimum links should be configured the same on both sides for optimal performance.
Topology
Figure 12-22: LAG minimum link
SW1
#configure terminal | Enter configure mode. |
(config)#interface po10 | Creating interface port-channel po10 |
(config-if)#port-channel min-links 4 | Configuring port channel minimum links as 4 (range is 2-32) |
(config-if)#commit | Commit the candidate configuration to the running Configuration. |
(config-if)#exit | Exit the configure mode |
Validation
SW1
#sh running-config interface po10
interface po10
switchport
bridge-group 1
switchport mode trunk
switchport trunk allowed vlan all
port-channel min-links 4
!
!
#show etherchannel
------------------------------------
% Lacp Aggregator: po10
% Min-links : 4
% Member:
xe4/1
xe4/2
xe4/3
xe4/4
------------------------------------
#show etherchannel summary
% Aggregator po10 100010
% Aggregator Type: Layer2
% Admin Key: 0010 - Oper Key 0010
% Link: xe4/4 (10072) sync: 1
% Link: xe4/1 (10069) sync: 1
% Link: xe4/2 (10070) sync: 1
% Link: xe4/3 (10071) sync: 1
--------------------------------------
SW2
#configure terminal | Enter configure mode. |
(config)#interface po10 | Creating interface port-channel po10 |
(config-if)#port-channel min-links 4 | Configuring port channel minimum links as 4 (range is 2-32) |
(config-if)#commit | Commit the candidate configuration to the running Configuration. |
(config-if)#exit | Exit the configure mode |
Validation
SW2
#show running-config interface po10
!
interface po10
switchport
bridge-group 1
switchport mode trunk
switchport trunk allowed vlan all
port-channel min-links 4
!
#show etherchannel
% Aggregator Type: Layer2
% Lacp Aggregator: po10
% Min-links: 4
% Member:
xe50/1
xe50/2
xe50/3
xe50/4
#show etherchannel summary
% Aggregator po10 100010
% Aggregator Type: Layer2
% Admin Key: 0010 - Oper Key 0010
% Link: xe50/4 (10072) sync: 1
% Link: xe50/1 (10069) sync: 1
% Link: xe50/2 (10070) sync: 1
% Link: xe50/3 (10071) sync: 1
Note: When a PO goes down due to the minimum links configured (number of minimum links is greater than the links aggregated to the PO).
SW1:
#sh int brief po10
Codes: ETH - Ethernet, LB - Loopback, AGG - Aggregate, MLAG - MLAG Aggregate
FR - Frame Relay, TUN -Tunnel, PBB - PBB Logical Port, VP - Virtual Port
CVP - Channelised Virtual Port, METH - Management Ethernet, UNK- Unknown
ED - ErrDisabled, PD - Protocol Down, AD - Admin Down,
IA - InActive
PD(Min L/B) - Protocol Down Min-Links/Bandwidth
DV - DDM Violation, NA - Not Applicable
NOM - No operational members, PVID - Port Vlan-id
Ctl - Control Port (Br-Breakout/Bu-Bundle)
HD - ESI Hold Timer Down
--------------------------------------------------------------------------------
Port-channel Type PVID Mode Status Reason Speed
Interface
--------------------------------------------------------------------------------
po10 AGG 1 trunk down PD(Min L/B) 0
#
#sh etherchannel
% Lacp Aggregator: po10
% Min-links: 4
% Protocol Down (Min L/B): True
% Member:
xe4/1
xe4/2
xe4/3
xe4/4
SW2:
#sh etherchannel
% Lacp Aggregator: po10
% Min-links: 4
% Protocol Down (Min L/B): True
% Member:
Xe50/1
Xe50/2
Xe50/3
xe50/4
#sh int brief po100
Codes: ETH - Ethernet, LB - Loopback, AGG - Aggregate, MLAG - MLAG Aggregate
FR - Frame Relay, TUN -Tunnel, PBB - PBB Logical Port, VP - Virtual Port
CVP - Channelised Virtual Port, METH - Management Ethernet, UNK- Unknown
ED - ErrDisabled, PD - Protocol Down, AD - Admin Down,
IA - InActive
PD(Min L/B) - Protocol Down Min-Links/Bandwidth
DV - DDM Violation, NA - Not Applicable
NOM - No operational members, PVID - Port Vlan-id
Ctl - Control Port (Br-Breakout/Bu-Bundle)
HD - ESI Hold Timer Down
--------------------------------------------------------------------------------
Port-channel Type PVID Mode Status Reason Speed
Interface
--------------------------------------------------------------------------------
po10 AGG 1 trunk down PD(Min L/B) 0
#
Last modified date: 10/12/2023