HP Systems Insight Manager - Manual (Page 185)

C Protocols used by HP SIM
HP SIM uses many different management protocol standards. This capability enables HP SIM to
provide management support for a wide array of manageable systems.
SNMP
The Internet Engineering Task Force (IETF), the standards-rating body for the worldwide Internet,
has defined a management protocol, SNMP , which has accumulated a major share of the market
and has the support of over 20,000 different products. SNMP has its roots in the Internet community.
The complexity of large international TCP/IP networks has provided the necessary incentive to
develop a standard method of managing devices on the network.
Within the SNMP framework, manageable network systems (routers, bridges, servers, and so on)
contain a software component called a
management agent . The agent monitors the various
subsystems of the network element and stores this information in a MIB . The agents enable the
device to generate traps, which can be sent to a trap destination server that is running HP SIM.
Conceptually, the MIB is a database that can be written to and read by a management application
using the SNMP protocol. The following MIB types include:
•
Internet Management MIBs.
These MIBs include MIB-II, RMON, and others and represent the core objects that are common
across the widest range of network devices implementing the Internet protocols. Examples of
these objects include network protocols such as TCP/IP and network systems such as Ethernet
network interfaces.
•
Vendor MIBs.
These MIBs represent objects that are unique to an individual vendor's product or product
line. Over 500 vendors and organizations have created their own vendor MIBs. HP was the
first personal computer company to develop a MIB-enabled SNMP management of system
hardware.
SNMP supports both read and write (GET and SET) commands on attributes. Some vendors do
not support the SET command because of the potential to allow an unauthorized person to alter
critical parameters on a network element. HP SIM primarily only uses the SNMP GET command.
SNMP is associated with TCP/IP and used for monitoring systems on Ethernet networks because
of its long association with the Internet.
Since its inception, SNMP itself has undergone several updates, including SNMP V2c and SNMP
V3. HP SIM supports the original V1-compliant agents and the compilation of V1 and V2 MIBs.
SNMP uses UDP port 161 for monitoring systems, while traps are received on port 162.
If your CMS is an HP-UX or Linux system, HP SIM might need to co-exist with other applications
using port 162. Use the following procedure to assign HP SIM to use a different port.
Procedure 49 Assigning HP SIM to use a different port
1. Open the globalsettings.props file located at /etc/opt/mx/config/
globalsettings.props.
2. Locate the SnmpTrapPortAddress property: SnmpTrapPortAddress=162 .
3. Modify this property by changing the port value to a different port number.
4. Restart HP SIM.
NOTE: HP SIM does not receive traps from the application using port 162 unless the application
is configured to forward traps to the port assigned to HP SIM.
NOTE: If the SnmpTrapPortAddress entry is deleted, HP SIM defaults to port 162.
HP SIM attempts SNMP communications based on the number of SNMP retries you specify and
only stops when the communication is successful or the number of retries is exceeded. HP SIM also
waits for SNMP responses between retries based on the timeout period. Finally, HP SIM can
communicate only through SNMP when the community string specified on the system and the
SNMP 185