SNMP (Simple Network Management Protocol) is a widely adopted protocol for managing and monitoring network devices and their functions. SNMP isn’t installed or enabled by default.
SNMP packages are available from the default package repositories and can be installed as root:
yum install net-snmp net-snmp-utils
Use the built in net-snmp-create-v3-user command to create an account to use for monitoring.
/usr/bin/net-snmp-create-v3-user
Enter a SNMPv3 user name to create:
smesnmp
Enter authentication pass-phrase:
mysecretpassword
Enter encryption pass-phrase: [press return to reuse the authentication pass-phrase]
mysecretpassword
The following will be displayed:
adding the following line to /var/lib/net-snmp/snmpd.conf: createUser smesnmp MD5 "mysecretpassword" DES mysecretpassword adding the following line to /etc/snmp/snmpd.conf: rwuser smesnmp
Now you can start the snmpd service and make sure it runs by default:
systemctl enable --now snmpd
The last step will be to allow through the local appliance firewall. Using your favorite editor (vim, nano, etc) edit the file /etc/sysconfig/iptables
Add the following two lines right before “-A RH-Firewall-1-INPUT -j REJECT –reject-with icmp-host-prohibited”
-A RH-Firewall-1-INPUT -p udp -m state --state NEW -m udp --dport 162 -j ACCEPT -A RH-Firewall-1-INPUT -p udp -m state --state NEW -m udp --dport 161 -j ACCEPT
After editing we can restart iptables to let those changes take effect
systemctl restart iptables
Now you’re all set, any system that uses SNMP can now query Access Anywhere, pull out metrics like cpu, memory, disk utilization as well as a range of other system metrics.