Not found ifconfig in CentOS?

Don't worry, if you have installed your CentOS/RedHat using minimal mode. The OS comes lightly without some of well-known binaries. Following how to install some of these necessary admin programs via yum:

1 - ifconfig:

# yum install net-tools

2 - killall:

yum install psmisc

3 - snmpwalk:

yum install net-snmp-utils