Shell Script To Remove All Keys Belonging To Hostname From a ~/.known_hosts File

# A simple shell script to clean (delete)  ~/.known_hosts file hostname entry.
# This is useful when remote server reinstalled or ssh keys are changed!
# -------------------------------------------------------------------------
# Copyright (c) 2007 nixCraft project <>
# This script is licensed under GNU GPL version 2.0 or above
# -------------------------------------------------------------------------
# This script is part of nixCraft shell script collection (NSSC)
# Visit for more information.
# -------------------------------------------------------------------------
[[ $# -eq 0 ]] && { echo "Usage: $0"; exit 1;}
ips=$(host "$host" | awk -F'address' '{ print $2}' | sed -e 's/^ //g')
ssh-keygen -R "$host"
for i in $ips
	ssh-keygen -R "$i"

How Do I Use This Script?

Simply run it as follows:

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1 comment… add one
  • J. E. Aneiros Mar 20, 2012 @ 21:53

    ips=$(host “$host” | awk -F’address’ ‘{ print $2}’ | sed -e ‘s/^ //g’)

    could be shorten to: ips=$(host “$host” | awk ‘/address/ { print $NF }’)

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