This issue affects administrators more than end-users but results in widespread outages.
Citrix Delivery Controllers (the brain of the operation) rely on a database (SQL). If the SQL database becomes unreachable, the Controllers switch to "Local Host Cache" mode. While this is a feature designed for resilience, it can sometimes cause connection failures if the LHC is corrupted or if the connection leasing files on the VDA are stale. citrix receiver connection issues