An SNMP agent is a powerful and complex software and, as such, may
be affected by flaws and security issues. We recommend that SNMP
access (161/udp,162/udp) be blocked at your firewall.
There are also some important changes that have been made in this release
of our package:
o the daemon now sets a PID file in /var/run/
o logging is now done directly to /var/log/net-snmpd.log instead
of sending stderr/stdout through syslog.
o the daemon is now started with the '-r'. This option prevents
snmpd from exiting if it doesn't have permission to read something.
This only occurs if you start snmpd on a high port as a non-root
root user.
o If you need to run snmptrapd, we've provided an init script
in /etc/init.d/snmptrapd, but the service is disabled by default.
SNMP traps should be avoided whenever possible because they are
unreliable (you should poll with snmpget instead) and snmptrapd
has been the source of many of the security problems with SNMP
so please don't run this unless you are sure of what you are doing.
To enable the service, run
chkconfig snmptrapd on
and create a configuration file named /etc/snmp/snmptrapd.conf.
Then, start the daemon with
rcsnmptrapd start
Logging is done to /var/log/net-snmpd.log.
For more information see the manpages for snmptrapd and snmptrapd.conf.
o Master AgentX support is enabled if you have modules in
/usr/lib/net-snmp/agents. The domain socket is created as
/var/run/agentx/master. You can change this to a network
interface if needed (see snmpd(1)). The snmpd init script
automatically detects and starts any sub-agents in placed into
/var/lib/net-snmp.
More documentation on the net-snmp package can be found in this directory
as well as the project's homepage: http://www.net-snmp.org/
