I have installed mrtg via yum on CentOS 7, and using cron job to load mrtg every 5 mins. Everything work fine but just snmp v3 graph no show up. I try to load the command LAND=C /usr/bin/mrtg /etc/mrtg/metg.cfg it will show an error “SNMP V3 libraries not found, SNMPV3 disabled.”. so, i installed all the net-snmp but still showing the error. I can’t find any suggestion on google. can anyone have the same problem ?