Howto Disconnect a Network Sevice without Stopping Entire Network in Ubuntu / Debian : Cutter

Cutter is tool used for disconnecting an TCP/IP connection. Some time Network administrators want to stop some specific services like ssh, chat. Cutter is a very useful utility for network administrators for blocking high bandwidth consuming services, peer-to-peer Service etc. It is a firewall administrators tool, so use in firewall / router machines.

$ sudo apt-get install cutter (or use synaptic package Manager)

cutter ipaddress1 [ port1 [ ipaddress2 [ port2 ] ] ]

You can use netstat for finding the connection.

Stop all ssh connection between 192.168.0.1 and server
$ sudo cutter 192.168.0.1 22

Stop all ssh connection between 192.168.0.1 and 192.168.0.2
$ sudo cutter 192.168.0.1 192.168.0.2 22

Stop all connections between 192.168.0.1 and server
$ sudo cutter 192.168.0.1

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