how to open UDP 161 port to allow only the SNMP monitoring server?

cebo_myeza · 06-10-2015, 02:11 AM

hi

i am working on a splunk project and i am using centos as my operating system, i just need help on how to allow only the SNMP monitoring server (SPLUNK) to connect to UDP 161 port in centos using CLI.And my monitoring host is 192.168.1.2/24

i have been using CLI command below but i am getting an error of bash: -A: command not found

-A INPUT -s 192.168.1.2/24 -p udp -m udp --sport 1024:65535 --dport 161 -m state --state NEW,ESTABLISHED -j ACCEPT

please help

roger_heslop · 06-10-2015, 03:47 AM

The rule that you've used looks like what you might see as a rule in /etc/sysconfig/iptables, but it's not a command. To apply that same rule, use the same syntax but starting with 'iptables'. For example:

Code:

iptables -A INPUT -s 192.168.1.2/24 -p udp -m udp --sport 1024:65535 --dport 161 -m state --state NEW,ESTABLISHED -j ACCEPT

That will change the running state of the firewall, but it's lost once restarted unless you save the configuration.

Code:

service iptables save

Habitual · 06-11-2015, 11:11 AM

Quote:

Originally Posted by cebo_myeza

Code:

-A INPUT -s 192.168.1.2/24 -p udp -m udp --sport 1024:65535 --dport 161 -m state --state NEW,ESTABLISHED -j ACCEPT

please help

Roger beat me to it

Go Roger, go!

Code:

iptables -A INPUT -s 192.168.1.2/24 -p udp -m udp --sport 1024:65535 --dport 161 -m state --state NEW,ESTABLISHED -j ACCEPT