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

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

AVC-based selective reanchoring

Updated: April 10, 2026

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Explains how AVC-based selective reanchorings manage client mobility between wireless controllers based on application traffic and AVC profiles.

An AVC-based selective reanchoring is a wireless client mobility mechanism that

  • reanchors clients as they roam between one controller to another and prevent depletion of available IP addresses, and

  • uses AVC profile-based statistics to determine if a client should be reanchored or deferred.

This is useful when a client is actively running a voice or video application defined in the AVC rules.

The reanchoring process also involves deauthentication of anchored clients. The clients get deauthenticated when they do not transmit traffic for the applications listed in the AVC rules while roaming between controllers.

Restrictions for AVC-based selective reanchoring

  • This feature operates only in local mode. FlexConnect and fabric modes are not supported.

  • This feature does not operate in guest tunneling scenarios or export anchor scenarios.

  • After reanchoring, the old IP address is retained until the IP address lease period ends.

Configure the flow exporter (CLI)

Define and configure a flow exporter to specify where and how NetFlow data is exported from the device.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Create a flow exporter and enter the flow exporter configuration mode.

Example:

Device(config)# flow exporter avc-reanchor
Note

You can use this command to modify an existing flow exporter too.
3.

Set the exporter as local.

Example:

Device(config-flow-exporter)# destination local wlc

Configure the flow monitor (CLI)

Set up a flexible NetFlow flow monitor to track traffic statistics.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Create a flow monitor and enter the flexible NetFlow flow monitor configuration mode.

Example:

Device(config)# flow monitor fm_avc
Note

You can use this command to modify an existing flow monitor too.
3.

Specify the name of an exporter.

Example:

Device(config-flow-monitor)# exporter avc-reanchor
4.

Specify the flow record to use to define the cache.

Example:

Device(config-flow-monitor)# record wireless avc basic
5.

Set the active flow timeout, in seconds.

Example:

Device(config-flow-monitor)# cache timeout active 60
6.

Set the inactive flow timeout, in seconds.

Example:

Device(config-flow-monitor)# cache timeout inactive 60

Configure the AVC reanchoring profile (CLI)

Configure traffic reanchoring for AVC by creating and updating an AVC reanchoring profile using commands.

Before you begin

  • Ensure that you use the AVC-Reanchor-Class class map. All other class-map names are ignored by Selective Reanchoring.

  • During boot up, the system checks for the existence of the AVC-Reanchor-Class class map. If it is not found, the system creates default protocols, such as jabber-video, WiFi-calling, and others. If the AVC-Reanchor-Class class map is found, configuration changes are not made. Updates to protocols saved to the startup configuration persist across reboots.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Configure the class map.

Example:

Device(config)# class-map AVC-Reanchor-Class
3.

Instruct the device to match with any of the protocols that pass through it.

Example:

Device(config-cmap)# match any
4.

Specify a match to the application name.

Example:

Device(config-cmap)# match protocol jabber-audio

You can edit the class-map configuration later to add or remove protocols such as jabber-video and wifi-calling if needed.

Configure the wireless WLAN profile policy (CLI)

Follow the procedure given below to configure the WLAN profile policy.

Note

Starting with Cisco IOS XE Amsterdam 17.1.1, IPv6 flow monitor is supported on Wave 2 APs. When NBAR runs in the controller and the AP operates in local (central switching) mode, you can attach two flow monitors per direction (input and output) and per IP version (IPv4 and IPv6) in a policy profile. In FlexConnect and fabric modes on Wave 2 APs, when NBAR runs on the AP, only one flow monitor per direction (input and output) and per IP version (IPv4 and IPv6) is supported.

Procedure

1.

Enter the global configuration mode.

Example:

Device# configure terminal
2.

Configure the WLAN policy profile and enters wireless policy configuration mode and disable the policy profile.

Example:

Device(config)# wireless profile policy default-policy-profile
Device(config-wireless-policy)# shutdown
3.

Disable central switching.

Example:

Device(config-wireless-policy)# no central switching
4.

Specify the name of the IPv4 ingress flow monitor.

Example:

Device(config-wireless-policy)# ipv4 flow monitor fm_avc input
5.

Specify the name of the IPv4 egress flow monitor.

Example:

Device(config-wireless-policy)# ipv4 flow monitor fm_avc output
6.

Specify the name of the IPv6 ingress and egress flow monitor.

Example:

Device(config-wireless-policy)# ipv6 flow monitor fm_v6_avc input
Device(config-wireless-policy)# ipv6 flow monitor fm_v6_avc output
7.

Enable the policy profile.

Example:

Device(config-wireless-policy)# no shutdown

Verify AVC reanchoring

Use the commands to verify the AVC reanchoring configuration:

Device# show wireless profile policy detailed avc_reanchor_policy

Policy Profile Name           : avc_reanchor_policy
Description                   : 
Status                        : ENABLED
VLAN                          : 1
Wireless management interface VLAN        : 34
!
.
.
.
AVC VISIBILITY                : Enabled
Flow Monitor IPv4
  Flow Monitor Ingress Name   : fm_avc
  Flow Monitor Egress Name    : fm_avc
Flow Monitor IPv6
  Flow Monitor Ingress Name   : Not Configured
  Flow Monitor Egress Name    : Not Configured
NBAR Protocol Discovery       : Disabled
Reanchoring                   : Enabled
Classmap name for Reanchoring
  Reanchoring Classmap Name   : AVC-Reanchor-Class
!
.
.
.
  -------------------------------------------------------

Device# show platform software trace counter tag wstatsd chassis active R0 avc-stats debug

Counter Name Thread ID Counter Value 
------------------------------------------------------------------------------
Reanch_deassociated_clients 28340 1 
Reanch_tracked_clients 28340 4 
Reanch_deleted_clients 28340 3 

Device# show platform software trace counter tag wncd chassis active R0 avc-afc debug

Counter Name Thread ID Counter Value 
------------------------------------------------------------------------------
Reanch_co_ignored_clients 30063 1 
Reanch_co_anchored_clients 30063 5 
Reanch_co_deauthed_clients 30063 4

Device# show platform software wlavc status wncd
Event history of WNCD DB:

AVC key: [1,wlan_avc,N/A,Reanc,default-policy-tag]
Current state : READY
Wlan-id : 1
Wlan-name : wlan_avc
Feature type : Reanchoring
Flow-mon-name : N/A
Policy-tag : default-policy-tag
Switching Mode : CENTRAL

Timestamp FSM State Event RC Ctx
-------------------------- ------------------- -------------------------- ---- ----
06/12/2018 16:45:30.630342 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:45:28.822780 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:28.822672 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:15.172073 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:45:12.738367 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:12.738261 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:01.162689 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:44:55.757643 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:55.757542 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:04.468749 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:44:02.18857 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:02.18717 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:38:20.164304 2 :READY 3 :FSM_AFM_SWEEP 0 2
06/12/2018 16:35:20.163877 2 :READY 1 :FSM_AFM_BIND 0 2
06/12/2018 16:35:18.593257 1 :INIT 1 :FSM_AFM_BIND 0 2
06/12/2018 16:35:18.593152 1 :INIT 24:CREATE_FSM 0 0

AVC key: [1,wlan_avc,fm_avc,v4-In,default-policy-tag]
Current state : READY
Wlan-id : 1
Wlan-name : wlan_avc
Feature type : Flow monitor IPv4 Ingress
Flow-mon-name : fm_avc
Policy-tag : default-policy-tag
Switching Mode : CENTRAL

Timestamp FSM State Event RC Ctx
-------------------------- ------------------- -------------------------- ---- ----
06/12/2018 16:45:30.664772 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:45:28.822499 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:28.822222 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:15.207605 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:45:12.738105 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:12.737997 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:01.164225 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:44:55.757266 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:55.757181 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:04.472778 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:44:02.15413 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:02.15263 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:38:20.164254 2 :READY 3 :FSM_AFM_SWEEP 0 2
06/12/2018 16:35:20.163209 1 :INIT 1 :FSM_AFM_BIND 0 2
06/12/2018 16:35:20.163189 1 :INIT 24:CREATE_FSM 0 0

AVC key: [1,wlan_avc,fm_avc,v4-Ou,default-policy-tag]
Current state : READY
Wlan-id : 1
Wlan-name : wlan_avc
Feature type : Flow monitor IPv4 Egress
Flow-mon-name : fm_avc
Policy-tag : default-policy-tag
Switching Mode : CENTRAL

Timestamp FSM State Event RC Ctx
-------------------------- ------------------- -------------------------- ---- ----
06/12/2018 16:45:30.630764 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:45:28.822621 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:28.822574 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:15.172357 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:45:12.738212 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:12.738167 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:45:01.164048 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:44:55.757403 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:55.757361 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:04.472561 3 :ZOMBIE 1 :FSM_AFM_BIND 0 2
06/12/2018 16:44:02.18660 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:44:02.18588 2 :READY 2 :FSM_AFM_UNBIND 0 0
06/12/2018 16:38:20.164293 2 :READY 3 :FSM_AFM_SWEEP 0 2
06/12/2018 16:35:20.163799 1 :INIT 1 :FSM_AFM_BIND 0 2
06/12/2018 16:35:20.163773 1 :INIT 24:CREATE_FSM 0 0

Device# show platform software wlavc status wncmgrd

Event history of WNCMgr DB:

AVC key: [1,wlan_avc,N/A,Reanc,default-policy-tag]
Current state : READY
Wlan-id : 1
Wlan-name : wlan_avc
Feature type : Reanchoring
Flow-mon-name : N/A
Policy-tag : default-policy-tag
Switching Mode : CENTRAL
Policy-profile : AVC_POL_PYATS

Timestamp FSM State Event RC Ctx
-------------------------- ------------------- -------------------------- ---- ----
06/12/2018 16:45:30.629278 3 :WLAN_READY 24:BIND_WNCD 0 0
06/12/2018 16:45:30.629223 3 :WLAN_READY 4 :FSM_BIND_ACK 0 0
06/12/2018 16:45:30.629179 3 :WLAN_READY 4 :FSM_BIND_ACK 0 0
06/12/2018 16:45:30.510867 2 :PLUMB_READY 22:BIND_IOSD 0 0
06/12/2018 16:45:30.510411 2 :PLUMB_READY 2 :FSM_WLAN_UP 0 0
06/12/2018 16:45:30.510371 2 :PLUMB_READY 1 :FSM_WLAN_FM_PLUMB 0 0
06/12/2018 16:45:28.886377 2 :PLUMB_READY 20:UNBIND_ACK_IOSD 0 0
!

AVC key: [1,wlan_avc,fm_avc,v4-In,default-policy-tag]
Current state : READY
Wlan-id : 1
Wlan-name : wlan_avc
Feature type : Flow monitor IPv4 Ingress
Flow-mon-name : fm_avc
Policy-tag : default-policy-tag
Switching Mode : CENTRAL
Policy-profile : AVC_POL_PYATS

Timestamp FSM State Event RC Ctx
-------------------------- ------------------- -------------------------- ---- ----
06/12/2018 16:45:30.664032 3 :WLAN_READY 24:BIND_WNCD 0 0
06/12/2018 16:45:30.663958 3 :WLAN_READY 4 :FSM_BIND_ACK 0 0
06/12/2018 16:45:30.663921 3 :WLAN_READY 4 :FSM_BIND_ACK 0 0
06/12/2018 16:45:30.511151 2 :PLUMB_READY 22:BIND_IOSD 0 0
06/12/2018 16:45:30.510624 2 :PLUMB_READY 2 :FSM_WLAN_UP 0 0
06/12/2018 16:45:30.510608 2 :PLUMB_READY 1 :FSM_WLAN_FM_PLUMB 0 0
06/12/2018 16:45:28.810867 2 :PLUMB_READY 20:UNBIND_ACK_IOSD 0 0
06/12/2018 16:45:28.807239 4 :READY 25:UNBIND_WNCD 0 0
06/12/2018 16:45:28.807205 4 :READY 23:UNBIND_IOSD 0 0
06/12/2018 16:45:28.806734 4 :READY 3 :FSM_WLAN_DOWN 0 0
!

AVC key: [1,wlan_avc,fm_avc,v4-Ou,default-policy-tag]
Current state : READY
Wlan-id : 1
Wlan-name : wlan_avc
Feature type : Flow monitor IPv4 Egress
Flow-mon-name : fm_avc
Policy-tag : default-policy-tag
Switching Mode : CENTRAL
Policy-profile : AVC_POL_PYATS

Timestamp FSM State Event RC Ctx
-------------------------- ------------------- -------------------------- ---- ----
06/12/2018 16:45:30.629414 3 :WLAN_READY 24:BIND_WNCD 0 0
06/12/2018 16:45:30.629392 3 :WLAN_READY 4 :FSM_BIND_ACK 0 0
06/12/2018 16:45:30.629380 3 :WLAN_READY 4 :FSM_BIND_ACK 0 0
06/12/2018 16:45:30.510954 2 :PLUMB_READY 22:BIND_IOSD 0 0
06/12/2018 16:45:30.510572 2 :PLUMB_READY 2 :FSM_WLAN_UP 0 0
06/12/2018 16:45:30.510532 2 :PLUMB_READY 1 :FSM_WLAN_FM_PLUMB 0 0
06/12/2018 16:45:28.886293 2 :PLUMB_READY 20:UNBIND_ACK_IOSD 0 0
06/12/2018 16:45:28.807844 4 :READY 25:UNBIND_WNCD 0 0
06/12/2018 16:45:28.807795 4 :READY 23:UNBIND_IOSD 0 0
06/12/2018 16:45:28.806990 4 :READY 3 :FSM_WLAN_DOWN 0 0
!