2 Replies Latest reply on Mar 14, 2018 12:57 AM by Littlefish

    How many License Servers should be registered in a load-balance on-premise installation?

    Littlefish Rookie

      We're currently deploying Ivanti Service Manager 2017.2 (On-Premise) and we're running into problems with the load-balanced aspects of the application. The License Server seems to be a single point of failure.


      A high level overview of what we've configured is as follows:


      UI servers (load-balanced with Azure Application Gateway):

        • WEB-01
        • WEB-02
        • WEB-03
        • WEB-04


      Processing servers (load-balanced internally by Ivanti Service Manager):

        • APP-01
        • APP-02
        • APP-03
        • APP-04


      The License Server on APP-01 has licenses installed for its MAC address and the target landscape has APP-01 registered. If the License Server service is stopped for any reason, the application fails gracefully.


      Screen Shot 2018-03-12 at 11.49.48.png

      If IIS is stopped on APP-01, an unhandled exception occurs:


      {"Timestamp":new Date(1520855495619),"ErrorCode":"WebException","IsLogged":true,"IsUIReady":true,"InternalMessage":null,"LogEntryId":"c5bbd82a59fe4365a176856eccf74ef3","Message":"Unhandled system exception. See exception details in the application log.","StackTrace":null,"ExceptionType":null}


      This message propagates to all application servers.


      The current working theory is that the License Server is dependent on IIS, so when another application server attempts to access the system the following chain of events occurs:


      1. Web/Application server e.g. APP-02 checks for a list of registered License Servers and finds APP-01
      2. APP-02 attempts to access the License Server APP-01 on port 80
      3. IIS routes the request through to the License Server and, if available, reports success


      If the License Server service is stopped but IIS is still available, the application gracefully handles the response from IIS and identifies there are no License Servers available. However, if IIS is unavailable there is no graceful response received and this presents itself as an Unhandled System Exception.


      We want Ivanti Service Manager to still be available in the event of a failure on APP-01 so what is the correct way to achieve this? Can multiple License Servers be registered against a landscape? If so, will the application server access them round robin?


      Kind Regards


      Kevin Coady