With Citrix Director 7.6, we can now monitor the Citrix license alerts from the Dashboard view. This new capability provides greater visibility into the licensing state of XenApp/XenDesktop to administrators.
In previous versions of XenApp and XenDesktop, if the correct licenses are not installed, users will get session rejections via the license policy engine. To avoid this limitation, Citrix introduced a new concept called Supplemental Grace Period (SGP) in XenApp/XenDesktop 7.6.
During the SGP, the license policy engine will grant unlimited connections, for about 15 days to allow for fixing the issue. An alarm is activated when the grace period expires, and the Delivery Controller can not checkout licenses to launch sessions from license server. SGP will be granted for overconsumption of licenses, i.e., there is no limitation in Citrix user count, whatever the concurrent user license we have. After the expiration of SGP, regular license limits are enforced.
Administrators can set a threshold for license usage. If the licenses consumed exceed the set threshold value, an alert will be generated and shown in the Licensing Server panel in Director. The default value OOB is set at 90% however it can be configured on the Delivery Controller by running the following XenDesktop PowerShell command to set a custom threshold.
Set-ConfigSiteMetadata – Name “LicensingAlertThreshold” –Value “90”
If the Citrix License server version is older than v11.12.1, the Controller cannot checkout licenses, as License server is incompatible. No alerts will be shown.