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New Member

Cisco 1760 firewall

Hi all! I've got a 1760 router which uses port forwarding (25, 80 and 443) for my internal network services. If, let's say, I try to open a FTP connection on the router, of course the connection will be refused. Is there a way to make the router DROP the packets instead of rejecting them? My Linux iptables configurations drop packets who fail the firewall test, so I would like the router to perform that behavior.

Commands for port forwarding:

ip nat inside source static tcp 80 int f0/0 80 (these work fine)

Cisco Employee

Cisco 1760 firewall

Hello Alexandre,

On your outside interface, try using the following command: no ip unreachables

Best regards,


New Member

Cisco 1760 firewall

Thanks for the fast reply, I issued the command and when, let's say, I try to open a FTP connection to the router (which should be refused), I get an ICMP message back. I don't want to receive a message back. Here's the releavant part of my config:

interface FastEthernet0/0

ip address

no ip unreachables

ip nat outside

ip virtual-reassembly

speed auto



New Member

Re: Cisco 1760 firewall

Hi Alexandre,

just supply the command from your interface that you would like to mute or dropped the packet,

# no ip unreacheable

Hope that would help your problem.


New Member

Cisco 1760 firewall

According to my previous post, that's what I did.

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