How to Monitor Remote Linux Machine using SNMP with Nagios on CentOS / Ubuntu

Nagios is used by Linux System Administrator for Network Monitoring Services. SNMP is abbreviated as Simple Network Management Protocol and a set of rules of network for managing complex networks in this tutorial we are dealing with the how to install and integrate the SNMP with the Nagios  to monitor the Remote Linux Machines.

Step-I ( Starting of Remote Linux Machines and Login using root Credentials)

Step-II (Installation of SNMP on respective Remote Linux Machine)

On CentOS / RHEL / Scientific Linux / Oracle Linux and all RPM based Systems

# yum install net-snmp

On Ubuntu Server / Debian / Linux Mint / Kali Linux and all DEB based systems

# apt-get install snmpd

Step-III (Create the snmpd.conf file and add the following lines on it)

# cd /etc/snmp
# cp snmpd.conf snmpd.conf.bak
# vim snmpd.conf

Add the following lines

# rocommunity public <Your Nagios IP Address>/<Port Number of Nagios>

:wq (Save and Exit)

Step-IV (Restart the snmpd Services)

On CentOS / RHEL / Scientific Linux / Oracle Linux 7/6/5 and all RPM based Systems

# service snmpd restart

On Ubuntu Server / Debian / Linux Mint / Pear OS / Kali Linux and all DEB based systems

# /etc/init.d/snmpd restart

Step-V (Edit the Firewall Settings)

On Firewall Settings White-list the SNMP UDP Port 161 to allow queries

Using IPtables command

# iptables -I INPUT -p udp –-destination-port 161 -j ACCEPT /etc/init.d/iptables save

Modifying host file

# vim /etc/hosts.allow

add the allowed address of Nagios host Here on port 161

Step-VI (Add SNMP daemon automatically on every system restart)

On CentOS / RHEL / Scientific Linux / Oracle Linux and all RPM based Systems

# chkconfig snmpd on

On Ubuntu Server / Debian / Linux Mint / Kali Linux and all DEB based systems

# /etc/init.d/snmpd start

Step-VII (Check whether SNMP is Configured Properly or Not)

# cd /usr/local/nagios/libexec
# ./check_snmp_storage.pl -H <Your  SNMP IP Address>

Final Results

• If it is Configured Properly : Above command return data
• If It is not Configured Properly : Above command doesn’t return data

That’s all for now.