Hi !
I want to use iptables firewall to block all incoming traffic except on several ports like www, smtp, pop.
It works all fine except for SNMP.
I want to use MRTG on localhost therefore I need the snmp port 161.
Therefore I did:
/sbin/iptables -I INPUT -p tcp --dport 161 -j ACCEPT
/sbin/iptables -I INPUT -p udp --dport 161 -j ACCEPT
/sbin/iptables -I INPUT -p tcp --dport 162 -j ACCEPT
/sbin/iptables -I INPUT -p udp --dport 162 -j ACCEPT
/sbin/iptables –P INPUT DROP
Now whenever I start mrtg from localhost and it wants to connect to my external IP-adress I get an error “no response received”
When I make /sbin/iptables –P INPUT ACCEPT it works.
I connect from the same host where the firewall and the snmp is running via the external IP.
Can you help me ??
Thank you,
Knom.
