ExtremeCloud IQ Controller provides the ability to deploy controllers in either of two modes: standalone or paired. The best practice is to deploy controllers in paired mode—hereafter referred to as high-availability—to
maintain service availability in the event of an outage. The controller Availability feature allows
both AP and client statistics to be available on both sides of the high-availability
configuration.
When configuring a controller pair for a high-availability deployment, consider the following information:
ExtremeCloud IQ Controller directly
balances capacity allocations across both controllers in a high-availability deployment. Adoption
Capacity is additive. For example, to support a 600 AP Capacity, you can purchase a 500
Device Capacity and a 100 Device Capacity. The availability pair shares the installed
capacity to the 600 limit. You can enter the entitlements on either system in the pair.
However, when purchasing capacity license SKUs, make sure that none of the license
blocks exceed the maximum adoption capacity for any individual system.
Controllers deployed as a high-availability pair must be the same ExtremeCloud IQ Controller model type.
Enable and configure NTP: Network Time settings on each appliance of an availability
pair must be identical for the configuration update process to be
successful.
Monitor the Availability Link Status and the Synchronization Status for an
availability pair from the Network Health widget on the ExtremeCloud IQ Controller Dashboard or from the user interface where controller Availability is configured.
Switch configuration and
statistics are synchronized between the primary and backup ExtremeCloud IQ Controller.
RF Domain database is
synchronized. RF Manager engines work from a synchronized database to preserve and
respect AP SmartRF state on failover.
Access points are not automatically upgraded. You
must initiate the AP upgrade manually after both controllers in an availability pair are
upgraded.
The following status data is replicated on the partner node of
an availability pair:
