Echelon LNS - Manual (Page 113)

LNS Programmer's Guide 99
engineered mode. This will ensure that the configuration of the network is always
synchronized with the information stored in the LNS database. However, you may want
to change the system management mode to lcaMgmtModeDeferConfigUpdates before
making extensive changes to a network, in order to minimize the impact of these changes
on the operation of the system.
For example, suppose a new floor or wing of a building is being added to the network,
and this addition affects a number of connections with devices that are already installed
on the network. You may find it more efficient to set the system management mode to
lcaMgmtModeDeferConfigUpdates, make all the necessary changes in the LNS
database, and then set the system management mode back to
lcaMgmtModePropagateConfigUpdates mode when you are ready to propagate those
changes to the network. This allows you to choose a period during which an interruption
in network operation would be less intrusive to do so.
Changing the System Management Mode
The system management mode is global and affects all clients that are accessing the
system. When changing the system management mode, consider the following:
1. When changing from lcaMgmtModeDeferConfigUpdates to
lcaMgmtModePropagateConfigUpdates, the network will be updated with any
changes to the database that have been made by any application since the system
management mode was set to lcaMgmtModeDeferConfigUpdates. Presumably,
whoever set the management mode to lcaMgmtModeDeferConfigUpdates had a
reason to do so. Propagating device updates while major changes are incomplete
could cause the network to function improperly. As a result, you should make sure
that all major network management operations initiated on the network by your
application or any other are complete when you change the system management
mode from lcaMgmtModeDeferConfigUpdates to
lcaMgmtModePropagateConfigUpdates.
2. Changing from lcaMgmtModePropagateConfigUpdates to
lcaMgmtModeDeferConfigUpdates also affects a variety of network management
operations. The following sections describe the things you need to be aware of in this
case.
Tracking Device Updates
Changing the system management mode from lcaMgmtModeDeferConfigUpdates to
lcaMgmtModePropagateConfigUpdates can take a considerable amount of time, since
LNS may have to update a large number of devices with pending updates. If a device has
been commissioned, you can determine if it will need to be updated by reading its
commission status. If an AppDevice object’s CommissionStatus property is set to
lcaCommissionUpdatesPending or lcaCommissionUpdatesFailed, then that device
will be updated when the system management mode is changed from
lcaMgmtModeDeferConfigUpdates to lcaMgmtModePropagateConfigUpdates.
You can monitor the progress of the device updates caused by such a management mode
change by subscribing your application to the OnCommission event. Invoke the
BeginCommissionEvent() method on the System object to do so. As devices are
updated and their commission status changes, the event will be fired.