When trying to initialize a PSM Session, the error "There are no available DPAs for this request" is seen.
One possible cause of this error is that the maximum number of sessions available on the DPAs may be in use.
Please verify if the issue has been caused by consuming the total available "Max Sessions" as configured on the DPA(s).
For Example: If there are 10 "Max Sessions" configured on the DPA, and there are 10 "Active Sessions" in use, the next attempt to initialize an 11th Session via the DPA will not complete.
The current licensing for the TPAM Appliance may be viewed under the /admin interface: System Status/Settings | System Status | PSM Concurrent Sessions License Limit.
Identify the current configuration on the DPA(s) regarding the "Max Sessions" option under /tpam interface: Management | DPA name | Details tab | Max Session.
Note that the TPAM appliance is limited to 20 concurrent sessions. Each DPA is limited to 150 concurrent sessions.
Review the "Active Sessions" from the /tpam interface: Management | Session Mgmt | Active Sessions screen. Determine if these are valid sessions, and if the total available "Max Sessions" have been consumed. It is possible there are sessions that have not been closed correctly and may be terminated.
Configure the "Max Sessions" appropriately for the required configuration. There must be enough available sessions to service the required number of concurrent sessions.