SignUp Client: Standalone Mode

When unable to contact its SignUp Service, the SignUp Client goes into standalone mode. In this mode, the PC is available for Immediate Reservations only, unless Scheduled Reservations were made for that PC before it went into standalone mode; these reservations will become due at the correct time for the correct user. Any Scheduled Reservations made after the PC went into standalone mode will not appear. Details of any sessions started while the Client is in standalone mode will be stored locally and sent to the SignUp Service once communication with it is restored.

The Client will accept any Logon ID and Password in standalone mode. However, if the SignUp Service comes back online while the session is still in progress, it checks the logon details, and if they are not valid, logs the user off. If a session is in progress when the Client first goes into standalone mode, the session will proceed as normal.

While in standalone mode, sessions are still subject to the Maximum Reservation Duration (this value is stored at the Client). Quota restrictions, however, are not enforced. This is because the Client needs to contact the SignUp Service to find out the what current User's quotas are, and how much of them have already been used.

The SignUp Client returns to normal functioning when it is notified by the SignUp Server that SignUp services are available again. Any sessions in progress when communication is restored will become subject to the usual limitations and quotas. Any user who has already exceeded a quota or limit will be given the Time Critical Warning and logged off as soon as the Critical Warning time expires.

Allowing SignUp Clients to operate in standalone mode poses a security risk. A user could, for example, start a reservation, then disconnect the PC from the network. Being unable to contact the server, the Client will go into standalone mode, potentially allowing the user to make use of the PC for longer than they would normally be allowed to.

To increase security, the ability for Clients to enter standalone mode can be turned on or off for each Computer Group at SignUp > Computer Groups > [selected Computer Group] > Advanced category (Allow Standalone property). If standalone mode is disallowed, only administrators will be able to log on to SignUp Clients that cannot contact their SignUp Server. If a session is in progress when the SignUp Client loses contact with the SignUp Server, the session will continue as normal, even if standalone mode is disallowed. Once the session ends, however, only administrators will be able to log on.

The SignUp Client will also go into standalone mode if it calls a Plug-in associated with the SignUp Service, and the Plug-in returns a failure.

Standalone mode protects the SignUp Client from a failure of the SignUp Service only. Failure of external systems, e.g. Library Management Systems, or other Pharos Services, e.g. the Database Service can still cause failures at the SignUp Client. If the system is configured to reassign Logon IDs via a Logon script (a possibility if users log on with a card swipe), then users will not be able to log on for Scheduled Reservations in standalone mode, because the server is not available to authenticate the Card ID and map it to the Patron’s real Pharos Logon ID.