When configured, the agent
starts when the system enters the multiuser state (traditionally
run-level 2). Upon startup, the agent reads configuration information
from its configuration files, then begins listening for SNMP
requests on the SNMP port (161). If configured
to send traps, the agent
also notifies the appropriate management stations that it is
running by sending a ``cold start'' trap to the systems
listed in the configuration file,
/etc/snmpd.trap.
SNMP is automatically enabled with
default configuration files when the system goes into multiuser
mode, if the TCP/IP protocol stack is configured on the system.
Even with these default configuration files, each site will
need to customize its environment. Do this in one of two ways: