Users Guide

149 | Software Licenses Dell Networking W-Series ArubaOS 6.4.x| User Guide
l Replacing a Controller
l Failover Behaviors
l Configuring Centralized Licensing
Primary and Backup Licensing Servers
Centralized licensing allows the primary and backup licensing server controllers to share a single set of licenses.
If you do not enable this feature, the master and backup master controller each require separate, identical
license sets. The two controllers acting as primary and backup license servers must use the same version of
ArubaOS and must be connected on the same broadcast domain using the Virtual Router Redundancy Protocol
(VRRP). Other client controllers on the network connect to the licensing server using the VRRP virtual IP address
configured for that set of redundant servers. The primary licensing server uses the configured virtual IP
address by default. However, if the controller acting as the primary licensing server becomes unavailable, the
secondary licensing server will take ownership of the virtual IP address, allowing licensing clients to retain
seamless connectivity to a licensing server.
Only one backup licensing server can be defined for each primary server.
The example below shows a primary and backup license server connected using VRRP. Licenses installed on
either the primary or backup server are shared between that pair of servers. If the primary and backup
controllers each had 16 AP licenses, 16 PEFNG licenses, and 16 xSec licenses installed, they would share a
combined pool of 32 AP, 32 PEFNG, and 32 xSec licenses. Any license client controllers connected to this pair of
redundant servers could also use licenses from this license pool.
Figure 10 Shared Licenses on a Primary and Backup Licensing Server
Communication between the License Server and License Clients
When you enable centralized licensing, information about the licenses already installed on the individual client
controllers are sent to the licensing server, where they are added into the server’s licensing table. The
information in this table is then shared with all client controllers as a pool of available licenses. When a client
controller uses a license in the available pool, it communicates this change to the licensing server master
controller, which updates the table before synchronizing it with the other clients.