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The Event and Alarm handling appliction (EVA) is a Fault Management application that provides support to applications and managers for sending and controlling events and alarms, and for control and transfer of logs in the system.
EVA is modular and provides two different management protocol
independent services. These two services are basic eva,
which provides event and alarm definition and sending, and
log which provides support for controlling logs in the
system, and for transferring logs to remote systems. There is
also a service called eva_log, which provides a
specialization of the generic log mechanism, for logging of
events and alarms. The basic eva can be used
independently of log. EVA defines an API that can be
used to make management protocol specific interfaces to EVA,
for example SNMP, CORBA, or HTTP interfaces. Currently, an SNMP
interface to the two generic services are defined.
EVA is designed to be used as an included application, which
means that it needs another application to include it, in order
to run. That application is an ordinary application which
starts the EVA services it needs in its supervision tree. The
services can either be started individually, or by using the
supervisor eva_sup.
EVA is designed to be a distributed global application, which means that the super application that includes EVA may be specified as a distributed application which runs at one node at a time only, with the other nodes as standby nodes. The basic EVA service - the eva server - is a global server, which means that clients can access the EVA functionality from any node.
EVA uses the Mnesia DBMS to store data. This means that Mnesia
must be running on all nodes where EVA can run, and that the
tables EVA uses are created and configured correctly. Each EVA
service provides a function that should be called to create the
tables, and to define the replicas for Mnesia. Each such function
is called create_tables* and takes one parameter that is
a list of nodes. The Mnesia tables will be replicated on these
nodes; some on disk, and some in RAM. It is important that
these nodes are the same as where the super application that
includes EVA is defined to run as a distributed application.
The following configuration parameters are defined for the EVA application; for more information about configuration parameters see application(3):
use_snmpea_log = true | false <optional>false.
The following MIBs are defined in EVA:
The MIBs are stored in the mibs directory. All MIBs are
defined in SNMPv2 SMI syntax. SNMPv1 versions of the mibs are
delivered in the mibs/v1 directory.
The compiled MIBs are located under priv/mibs, and the
generated .hrl files under the include directory.
To compile a MIB that IMPORTS an EVA MIB,
give the option {il, ["eva/priv/mibs"]} to the MIB
compiler.
The MIBs are loaded into the agent when the services are started.
eva(3), eva_log(3), eva_server(3), eva_sup(3), eva_log_snmp(3), eva_snmp_adaptation(3), log(3), log_snmp(3), log_snmpea(3), snmp(6)