Setting up redundancy

The nControl redundancy system allows a standby unit to replace an active unit on the network if it stops functioning.

When the system is used, the configuration settings from the active unit are automatically copied to the standby unit to keep them synchronized. The two units are responsible for a single role. There are two main modes of operation:

• One nControl is the primary unit and a second nControl is the backup unit. The primary unit is active and the backup unit is in standby mode. The backup unit continuously monitors the primary unit and synchronizes its files with the primary unit. In the event the primary unit fails, the backup unit will take over. If the primary unit starts functioning, it will take over from the backup unit.

  This mode is recommended when you want to prioritize the use of one unit over another. The primary unit may have a serial device attached, for example, and you want this device to be available to your project whenever possible. If a switchover is made to the backup unit, but then the primary unit subsequently starts functioning, you want to switch back to the primary unit immediately, so the serial device can be used.

• Two nControl units are set up as peers. One unit is active and the other unit is in standby mode. The unit in standby mode continuously monitors the active unit and synchronizes its files with the active unit. In the event the active unit fails, the unit in standby mode will take over. If the failed unit comes back online, it will run in standby mode and monitor the active unit, ready to take over if there is another failure.

If Kiosk users are connected to a project hosted on an nControl unit when it fails, they will be automatically connected to the project on the backup unit after a short delay.

Notes:

• By default, when one nControl unit takes over from another, the controls in the project (knobs, faders etc.) are reset to their default values. If you would like the controls to be set to the most recent values displayed in Kiosk, you need to change a setting in NWare: On the NWare File menu, click Project Properties, click Advanced, and then select the Auto save settings check box.
• It is important that you test the redundancy system carefully before using it in an installation. If the switchover to the standby unit does not work, users will be unable to connect to the NWare project.
• You can set up a redundancy system to use an nControl unit and an nTouch 180 unit, rather than units of the same type. However, the NWare project must be fully compatible with both units, otherwise it will not function properly when the backup unit takes over.

To set up redundancy when using a primary unit and a backup unit

1. Power up both the nControl units.
2. Connect to the web interface on the backup unit.
3. On the Special screen, under Redundancy, type the IP address of the primary nControl unit in the Peer Unit Address box.
4. In the Timeout box, type the number of seconds to wait after the backup unit has lost contact with the primary unit before the backup unit takes control.

   Waiting for a period of time allows the primary unit to start and load the project after a normal power cycle, preventing the backup unit from taking over automatically. It also allows for when communications between the primary and backup unit stop for a few seconds because of a slow network, for example.

5. Click Set to confirm the action.

   You will be asked to log on.

6. Specify your username and password. The default username is superuser; it has no password.
7. Restart the backup nControl unit.

To set up redundancy when using two units as peers

1. Power up both the nControl units.
2. Connect to the web interface on the first unit.
3. On the Special screen, under Redundancy, type the IP address of the second nControl unit in the Peer Unit Address box.
4. In the Timeout box, type the number of seconds to wait after this unit has lost contact with the other unit before this unit takes control.

   The same value can be specified on both units. This is because if they both start at the same time, they will negotiate to determine which unit will be active and which will operate in standby mode.

5. Click Set to confirm the action.

   You will be asked to log on.

6. Specify your username and password. The default username is superuser; it has no password.
7. Restart the first nControl unit.
8. Repeat steps 2-7 for the second nControl unit.