Users Guide

Setup and Administration 27
Configuring the SNMP Agent on Systems Running Supported Red Hat Enterprise Linux
Server Administrator uses the SNMP services provided by the ucd-snmp or net-snmp SNMP agent.
You can configure the SNMP agent to change the community name, enable Set operations, and send
traps to a management station. To configure your SNMP agent for proper interaction with management
applications such as IT Assistant, perform the procedures described in the following sections.
NOTE: See your operating system documentation for additional details on SNMP configuration.
SNMP Agent Access Control Configuration
The management information base (MIB) branch implemented by Server Administrator is identified by
the OID 1.3.6.1.4.1.674. Management applications must have access to this branch of the MIB tree to
manage systems running Server Administrator.
For Red Hat Enterprise Linux operating systems, the default SNMP agent configuration gives read-only
access for the "public" community only to the MIB-II "system" branch (identified by the 1.3.6.1.2.1.1 OID)
of the MIB tree. This configuration does not allow management applications to retrieve or change Server
Administrator or other systems management information outside of the MIB-II "system" branch.
Server Administrator SNMP Agent Install Actions
If Server Administrator detects the default SNMP configuration during installation, it attempts to modify
the SNMP agent configuration to give read-only access to the entire MIB tree for the "public" community.
Server Administrator modifies the /etc/snmp/snmpd.conf SNMP agent configuration file in two ways.
The first change is to create a view to the entire MIB tree by adding the following line if it does not exist:
view all included .1
The second change is to modify the default "access" line to give read-only access to the entire MIB tree
for the "public" community. Server Administrator looks for the following line:
access notConfigGroup "" any noauth exact systemview none none
If Server Administrator finds the line above, it modifies the line so that it reads:
access notConfigGroup "" any noauth exact all none none
These changes to the default SNMP agent configuration give read-only access to the entire MIB tree for
the "public" community.
NOTE: To ensure that Server Administrator is able to modify the SNMP agent configuration to provide proper
access to systems management data, it is recommended that any other SNMP agent configuration changes be
made after installing Server Administrator.
Server Administrator SNMP communicates with the SNMP agent using the SNMP Multiplexing
(SMUX) protocol. When Server Administrator SNMP connects to the SNMP agent, it sends an object
identifier to the SNMP agent to identify itself as a SMUX peer. Because that object identifier must be
configured with the SNMP agent, Server Administrator adds the following line to the SNMP agent
configuration file, /etc/snmp/snmpd.conf, during installation if it does not exist:
smuxpeer .1.3.6.1.4.1.674.10892.1