Netscape NETSCAPE CONSOLE 6.0 - MANAGING SERVERS, Manual

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SNMP Basics
Chapter 11 Using SNMP to Monitor Servers 211
The Windows NT operating system includes an SNMP master agent. Netscape
Administration Server employs this service when utilizing SNMP. You can access
and operate this master agent through the Network control panel. In the UNIX
environment, the master agent is installed with Administration Server.
Some UNIX operating systems support an extended version of SNMP called the
SNMP multiplexing protocol (usually known as SMUX). This allows Netscape
servers to operate without a master agent. For those versions of UNIX that do not
support SMUX, you can use Netscape Console to manage the master agent that
Netscape provides.
How SNMP Works
A managed device, such as a server, stores its configuration and management
settings as variables. Some of these variables can be read and changed over SNMP
while others cannot. The variables that the master agent can read and change are
called managed objects. Managed objects are defined in a tree-like hierarchy
known as a management information base (MIB).
Each Netscape server provides a management information base (MIB) for use in
SNMP communication. This MIB contains managed objects pertaining to the
server’s operation. Each managed object has a unique object identifier. A server can
report significant events to the network management station by sending “trap”
messages (often called just “traps”) containing these object identifiers. In addition,
the network management station can initiate communication, and then specify one
or more object identifiers when querying a server’s MIB for data. The network
management station can also remotely change variables in the MIB by specifying
an object identifier and sending its new value.
Netscape MIBs
Each Netscape server has its own MIB. All Netscape MIBs are located in the
<server root>/plugins/snmp
directory.
A server’s MIB contains variable definitions used when managing that particular
server. Some of these variables can be modified over SNMP by a network
management station while others are flagged as read-only or inaccessible. See your
server’s documentation for detailed information about its management variables.