ems.5 (2012 03)

ems(5) ems(5)
NAME
ems - Description of Event Monitoring Service (EMS)
DESCRIPTION
EMS (Event Monitoring Service) is a monitoring service that polls a system resource and sends
messages when events occur. An event is something you want to know about. For example, you may
want to be alerted when a disk goes down or when available filesystem space falls below a certain level.
EMS allows you to configure what you consider an event for any given system resource (disk, filesystem
space, network interfaces).
The advantage EMS has over built-in monitors is that requests can be made to send events to a wide
variety of software using multiple protocols (opcmsg, SNMP, TCP, UDP).
EMS consists of three components:
Framework The framework starts and stops the monitors, stores information used by the monitors,
directs monitors where to send events. This framework consists of the Registrar, the resource dictionary,
and the EMS API.
A standard API provides a way to plug in new monitors as they become available, or to write your own
monitors; see the document "Writing Monitors for the Event Monitoring Service (EMS)" available from the
high-availability web site: "http://www.hp.com/go/ha".
Monitors are applications written to gather and report information about specific resources on the sys-
tem. When you make a request to a monitor, it polls the system information and sends a message to the
framework, which then interprets the data to determine if an event has occurred and sends messages in
the appropriate format.
A set of monitors are shipped with EMS: disk, cluster, network interface, and system resource monitors.
Configuration interface Runs under SAM (System Administration Manager).
EMS Directories and Files
EMS files live in
/etc/opt/resmon
and /opt/resmon. The following is a description of files and
directories that might help you as you navigate through EMS.
/etc/opt/resmon/config
A file that sets the restart interval for monitor persistence.
/etc/opt/resmon/dictionary
A directory that contains resource dictionaries for the various monitors. The disk monitor resources are
listed in
diskmond.dict and the cluster, network, and system resource monitors are in the
mibmond.dict. If you were writing your own monitor, the dictionary would go in this directory.
/etc/opt/resmon/lbin
A directory where all the monitor daemons live. Some important daemons in the directory:
p_client restarts any failed monitors based on information in the config file
registrar handles passing monitoring requests to the correct monitors, and sending qualify events out
in the correct protocol format.
/etc/opt/resmon/log
A directory of log files used by EMS. The most interesting for troubleshooting are:
api.log stores api calls made by monitors.
client.log stores calls made by clients, such as MC/ServiceGuard or the SAM interface to EMS.
/opt/resmon/resls
HP-UX 11i Version 3: March 2012 − 1 − Hewlett-Packard Company 1