Cisco Catalyst 9800 Series Wireless Controller Software Configuration Guide, Cisco IOS XE 26.1.x

PDF

Cisco Catalyst 9800 Series Wireless Controller Software Configuration Guide, Cisco IOS XE 26.1.x

CAPWAP LAG support

Updated: April 10, 2026

Want to summarize with AI?

Log in

Explains how CAPWAP Link Aggregation (LAG) enables redundancy, simplifies configuration, and ensures continued connectivity between controllers and access points.

A CAPWAP LAG support feature is a controller-access point connectivity mechanism that

  • enables link aggregation of controller ports.

  • allows automatic failover of traffic if a port fails, and

  • simplifies controller configuration by removing the requirement to configure primary and secondary ports for each interface.

Link aggregation ensures that traffic is redirected automatically to a functioning port if one controler port fails. With at least one controller port operating, network connectivity is maintained, APs stay connected and wireless clients remain operational.

CAPWAP (Control and Provisioning of Wireless Access Points) is a protocol that manages communication between wireless LAN controllers and access points.

Link Aggregation refers to using multiple network connections in parallel to increase throughput and provide redundancy.

Supported models

The CAPWAP LAG support feature applies to APs with multiple Ethernet ports for CAPWAP.

  • 11AC APs with dual Ethernet ports require CAPWAP AP LAG support for their data channels.

  • By default, the second port on Cisco Aironet 1850, 2800, and 3800 Series APs is used for link aggregation. If you disable LAG, you can use the LAG port as an RLAN port.

These APs use LAG port as an RLAN (Remote LAN) port:

  • Cisco Aironet 1852E Access Point

  • Cisco Aironet 1852I Access Point

  • Cisco Aironet 2802E Access Point

  • Cisco Aironet 2802I Access Point

  • Cisco Aironet 3802E Access Point

  • Cisco Aironet 3802I Access Point

  • Cisco Aironet 3802P Access Point

  • Cisco Catalyst 9136I Access Point

Note

The CAPWAP LAG feature do not support the Cisco Catalyst 9176I and Cisco Catalyst 9176D1 APs.

Restrictions for CAPWAP LAG support

Ensure these requirements are met when using CAPWAP LAG support.

  • APs must be specifically enabled for CAPWAP AP LAG support.

  • CAPWAP data does not support IPv6.

  • Do not enable Datagram Transport Layer Security (DTLS) when you enable LAG.

  • CAPWAP LAG does not work with APs behind Network Address Translation (NAT) or Port Address Translation (PAT).

Enable CAPWAP LAG support on controller (GUI)

Enable LAG support for APs using the controller GUI.

Procedure

1.

Choose Configuration > Wireless > Wireless Global.
2.

Check the AP LAG Mode check box.
3.

Click Apply.

Enable CAPWAP LAG support on controller (CLI)

Enable LAG support for all APs on the controller using CAPWAP.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Enable CAPWAP LAG support on the controller.

Example:

Device(config)# ap lag support
Note

After executing this command, this warning statement is displayed:

Changing the lag support will cause all the APs to disconnect. Thus, all APs with LAG capability reboots and joins the enabled CAPWAP LAG.
3.

Returns to privileged EXEC mode. Alternatively, you can also press Ctrl-Z to exit global configuration mode.

Example:

Device(config)# end

Enable and disable CAPWAP LAG globally on controller

If the CAPWAP LAG is enabled globally on the controller, these events occur:

  • The AP joins the controller.

  • The AP exchanges its CAPWAP support.

  • LAG mode starts, if LAG is enabled on AP.

If the CAPWAP LAG is disabled globally on the controller, these events occur:

  • The AP joins the controller.

  • The AP exchanges its CAPWAP support.

  • The AP receives the LAG configuration if LAG is already enabled on the AP.

  • The AP reboots.

  • The AP joins again with LAG disabled.

Enable CAPWAP LAG for an AP profile (GUI)

Enable LAG mode for a CAPWAP AP profile to improve reliability and throughput using GUI.

Procedure

1.

Choose Configuration > Tags (and) Profiles > AP Join.
2.

Click Add.
3.

Under the General tab, enter the Name of the AP Profile and check the LAG Mode check box to set the CAPWAP LAG for the AP profile.

4.

Click Apply to Device.

Enable CAPWAP LAG for an AP profile (CLI)

Enable CAPWAP LAG on an AP profile to improve data throughput and provide redundancy for associated APs.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Configure an AP profile and enter the AP profile configuration mode. ap profile ap-profile .

Example:

Device(config)# ap profile xyz-ap-profile
Note

When you delete a named profile, the APs associated with that profile do not revert to the default profile.
3.

Enable CAPWAP LAG for an AP profile.

Example:

Device(config-ap-profile)# lag
4.

Exit configuration mode and return to privileged EXEC mode.

Example:

Device(config-ap-profile)# end

Disable CAPWAP LAG for an AP profile (CLI)

Disable CAPWAP LAG for a specified AP profile using commands.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Configure an AP profile and enter the AP profile configuration mode.

Example:

Device(config)# ap profile xyz-ap-profile
Note

When you delete a named profile, the APs associated with that profile do not revert to the default profile.
3.

Disable CAPWAP LAG for an AP profile.

Example:

Device(config-ap-profile)# no lag
4.

Exit configuration mode and return to privileged EXEC mode.

Example:

Device(config-ap-profile)# end

Disable CAPWAP LAG support on controller

Disable LAG support for the CAPWAP protocol using commands.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Disable CAPWAP LAG support on the controller .

Example:

Device(config)# no ap lag support
Note

All APs with LAG capability reboots and joins the disabled CAPWAP LAG.
3.

Exit configuration mode and return to the privileged EXEC mode.

Example:

Device(config)# end

Verify CAPWAP LAG support configurations

To verify the global LAG status for all Cisco APs, use the command:

Device# show ap lag-mode

AP Lag-Mode Support Enabled

To verify the AP LAG configuration status, use the command:

Device# show ap name config general

Cisco AP Identifier : 0008.3291.6360
Country Code : US
Regulatory Domain Allowed by Country : 802.11bg:-A 802.11a:-AB
AP Country Code : US - United States
::
AP Lag Configuration Status : Enabled/Disabled
Has AP negotiated lag based on AP capability and per AP config

Configure bulk AP provisioning (GUI)

Use bulk AP provisioning to configure multiple parameters, such as admin status, floor location, geolocation, and high availability settings, for several APs at once.

Procedure

1.

Choose Configuration > Wireless > Bulk AP Provisioning.

View the current tasks and their status.
2.

Click Start a workflow to create an AP Provisioning task to start a new bulk AP provisioning task.
3.

In the Select AP page, configure the following:

  1. Change the name of the task.

  2. Select the APs you wish to provision.

  3. Click Next.
4.

In the Select Parameters page, configure the following as required:

  1. Change the admin status using the drop-down list.

  2. Enter the location.

  3. Enter the above ground level height in meters. The range is from -100 to 1000.

  4. Enter the tolerance as uncertainty height in meters. The range is from zero to 100.

  5. Enter the cable length in meters. The range is from one to 100. The default is 10.

    Note

    Keep the default value of 10 meters when using a Cisco provided external antenna. This option is available only on models that support external antennas.

  6. Enter the floor ID.

  7. Enter the name and management IP address of the primary, secondary, and tertiary controllers.

  8. Click Next.
5.

In the Summary page, click Apply after confirming the changes.

You can view the task status as it progresses from provisioning to completion. After selecting the task, you can view the number of configurations applied and not applied to each selected AP.

Activate tracking for deactivated infrastructure devices (GUI)

Use this procedure to initiate tracking for an inactive infrastructure device that has been deactivated. After the switch or AP becomes active, CUCM tracks its status and provides a list of endpoints that associate to the switch or AP.

Note

The controller synchronization process only adds new APs to the list and does not remove APs if they are not found.

To remove APs from the infrastructure list, mark them as inactive. After they are marked as inactive, navigate to the inactive page and delete the APs.

Because APs are stored independently in the database, controllers and APs are not directly associated. If you delete a controller, CUCM does not track AP or controller associations. APs learned from the controller stay in the system.

Before you begin

Configure Location Awareness. For more information, refer to the "Location Awareness" chapter in the System Configuration Guide for Cisco Unified Communications Manager.

Procedure

1.

In Cisco Unified CM Administration, choose Advanced Features > Device Location Tracking Services > Switches and Access Points.
2.

From Related Links, choose Inactive Switches and Access Points and click Go.

The Find and List Inactive Switches and Access Points window displays the infrastructure devices that are not being tracked.
3.

Select the switch or AP for which you want to initiate tracking.
4.

Click Reactivate Selected.