Setting up Cisco 3504 series wireless controller redundancy
The new Cisco AIR-CT3504 wireless controller support High Availability with SSO (Stateful SwitchOver). In this setup one WLC acts as primary unit, the other as secondary unit (so-called Active/Hot Standby). The wireless controllers have a dedicated redundancy port which must be connected with a standard Cat.6 patch cord.
First the primary unit must configured with a management, redundancy-management and its peer-redundancy-management (i.e. the second WLC) IP address.
(Cisco Controller) >config interface address management (IP-WLC#1) (SUBNET) (GATEWAY) (Cisco Controller) >config interface address redundancy-management (RED-IP-WLC#1) peer-redundancy-management (RED-IP-WLC#2)
Then the primary unit must be configured as primary and the redundancy mode must be set to sso. Note: This will reboot the wireless controller.
(Cisco Controller) >config redundancy unit primary (Cisco Controller) >config redundancy mode sso WARNING: 1. If peer unit's management and/or redundancy management entries are present as mobility members please remove them before enabling redundancy. All unsaved configuration will be saved. And the system will be reset. Are you sure? (y/n)y Configuration Saved! System will now reboot!
The next step is to setup the secondary wireless controller with a management, redundancy-management and its peer-redundancy-management (this time the primary WLC) IP address.
(Cisco Controller) >config interface address management (IP-WLC#2) (SUBNET) (GATEWAY) (Cisco Controller) >config interface address redundancy-management (RED-IP-WLC#2) peer-redundancy-management (RED-IP-WLC#1)
Similar to the primary unit the secondary unit must be configured as secondary and the redundancy mode must be set to sso. Note: This will reboot the wireless controller.
(Cisco Controller) >config redundancy unit secondary (Cisco Controller) >config redundancy mode sso WARNING: 1. If peer unit's management and/or redundancy management entries are present as mobility members please remove them before enabling redundancy. All unsaved configuration will be saved. And the system will be reset. Are you sure? (y/n)y Configuration Saved! System will now reboot!
After a restart the wireless controllers will look for each others peer and sync the configuration, Access Point license count, etc. The status of can be verified with:
(Cisco Controller) >show redundancy summary Redundancy Mode = SSO ENABLED Local State = ACTIVE Peer State = STANDBY HOT Unit = Primary Unit ID = DC:F7:19:hh:hh:hh Redundancy State = SSO Mobility MAC = DC:F7:19:hh:hh:hh Redundancy Port = UP BulkSync Status = Complete Average Redundancy Peer Reachability Latency = 173 Micro Seconds Average Management Gateway Reachability Latency = 2914 Micro Seconds
On the second wireless controller the status should be verified as well:
(Cisco Controller-Standby) >show redundancy summary Redundancy Mode = SSO ENABLED Local State = STANDBY HOT Peer State = ACTIVE Unit = Secondary (Inherited AP License Count = 13) Unit ID = DC:F7:19:hh:hh:hh Redundancy State = SSO Mobility MAC = DC:F7:19:hh:hh:hh Redundancy Port = UP Average Redundancy Peer Reachability Latency = 160 Micro Seconds Average Management Gateway Reachability Latency = 3516 Micro Seconds
The configuration should be verified by powering the primary unit off. The secondary unit should recognize that the primary unit failed and should do a so-called WLC switch over as shown below:
(Cisco Controller-Standby) > HA completed successfully, WLC switch over detection time : ~360 msec and APs switch over time : ~0 msec (Cisco Controller) >
Note: the CLI prompt changed from (Cisco Controller-Standby) into (Cisco Controller) after a successful switch over.