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T H E U N I N T E R R U P T I B L E P O W E R P R O V I D E R
Network Management Cards – User Manual
34003676EN/AA
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4 Supervision / Administration via SNMP
4.1 SNMP offer operation principle
UM-Client, on protected server boot, subscribes itself automatically to the SNMP agent (in the
manager table) and sends the essential data:
◗
IP address of the server on which it is installed
, to be notified by the SNMP agent of any power
events (SNMP traps).
◗
Time required to shutdown the server
(UM-Client Shutdown Duration, configurable with the UM-
Editor utility, installed with UM-Client):
The SNMP agent takes into account the longest shutdown time of all UM-Clients subscribed (which
is the
Shutdown Duration
of the SNMP agent) to manage UPS shutdown without affecting any of
the connected UM-Clients.
In case of a major power event, UM Client receives the traps (SNMP messages) from the SNMP agent
and regularly checks agent accessibility. The most important messages can generate actions and are
sent back to the administrator and users via the network.
When the server shuts down, UM-Client unsubscribes itself from the manager table (the “Protocol”
field changes to “invalid”).
4.1.1 Shutdown
criteria
During an extended power failure, three criteria may cause the server shutdown procedure to be
initiated. If several criteria are selected, the first criterion encountered will launch the shutdown
procedure.
At the end of the shutdown procedure, when all servers have been shut down, the UPS may shut
down to avoid unnecessary discharge of its batteries, depending on its configuration.
4.1.1.1 Backup time before initiating the shutdown procedure (Shutdown timer)
When the UPS switches to battery, the
SNMP agent
starts the Shutdown Timer countdown and
launches the system shutdown procedure at the end of the countdown.
This value must be chosen so that users have time to complete their tasks and disconnect, without
exceeding battery backup time.
By default, this value is set to 30 minutes.
Configuration with UM-C), UM-Vision or SET SNMP
Note 1:
UM-Client also manages its own Shutdown Timer (configurable with UM-Editor), triggered by reception
of the SNMP trap “Mains loss”.
Note that if this criterion is selected to initiate system shutdown, automatic system reboot when power
is restored is not guaranteed (e.g. power restoration if only this system was shut down). We
recommend leaving this parameter at a value greater than the one of the Shutdown Timer of the
SNMP agent.
By default, this value is set to 31 minutes.
Note 2:
For devices without UM-Clients (backup units, routers and other internetworking equipment,
automated systems, etc.), in the case of extended backup time, the SNMP agent will launch a UPS
shutdown at the end of the Shutdown Timer. To avoid this behavior, a Shutdown Timer value longer
than the maximum installation backup time must be programmed.
