The Easiest Way to Enable SNMP on Linux CentOS
1. After login, change to root:
su –
2. Install SNMP package using YUM:
yum install net-snmp
3. Configure SNMP parameter
echo rocommunity community_string mrtg.yourhost.com > /etc/snmp/snmpd.conf
4. Turn on the default SNMP service on system reboot
chkconfig snmpd on
5. Start SNMP service
service snmpd start
Finally, of course, you will need to open UDP Port 161 on the firewall in order to get SNMP working.