SNMP Subagent Programmer's Guide

Introduction to Subagent Programming
SNMP Subagent Programmer’s Guide—119728 1-11
PEER Subagent Portability
Installing Subagents
After a subagent has been debugged and bound with PEERLIBO, it is ready for
production use. Simply install the executable subagent file on the production NonStop
system and compile and install the MIB definition on manager stations that will be using
your subagent.
Before a manager station can access objects in your subagent’s MIB, it needs to be
configured to meet security criteria imposed by the NonStop agent and your subagent:
•
The community name and IP address associated with the manager station must
appear in one of the NonStop agent’s authentication table entries. The NonStop
agent passes manager requests to your subagent only if the manager station from
which they arrive has an entry in the authentication table. Refer to the SNMP
Configuration and Management Manual for information on how to configure
authentication table entries.
•
By default, manager requests forwarded to subagents from the NonStop agent are
processed in accordance with the access attributes of individual MIB objects.
Managers can perform Get and GetNext operations on read-only MIB objects and
Get, GetNext, and Set operations on read-write objects. However, you can encode
your subagent to respond to a request to access a MIB object, independently of its
access attributes, only if it contains a particular password and originates from a
specific IP address. This option, known as “subagent request authentication,”
requires that the password appear as follows in the manager station community
string:
agent-community-string::subagent-password
The agent community string must appear in one of the NonStop agent’s
authentication table entries. The agent community string, a double colon, and the
subagent password must appear in the manager station’s configuration. The agent
community string can contain from 0 to 50 printable bytes, and cannot contain
successive colons. The total manager station community string can contain 0 to 255
bytes.
Also, configure the manager stations so that their timeouts and retries accommodate
times when the NonStop agent is handling multiple requests simultaneously. Try setting
the timeout value to 5 to 9 seconds and the retry value to 0 or 1.
PEER Subagent Portability
The developers of the Subagent Toolkit implemented it by porting components of the
PEER Network, Inc., Object Development Environment (ODE). You can convert
subagents developed using the ODE to run in the NonStop environment by making some
changes to the subagent source code:
•
Any operating system differences, such as procedure calls and file system
operations, need to be addressed.
•
The management function mgmt_select_mask() is not supported. Instead, you use
mgmt_read_nowait() to perform nowaited operations.