DynDNS and kernel stripping for Ubuntu

remove_old_kernels.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+# Remove all but the latest $keep kernels (and headers)
+#
+keep=2
+sudo aptitude purge $( 
+	for i in linux-headers-[0-9]*[0-9] linux-headers-[0-9]*generic linux-image-[0-9]* linux-image-extra-[0-9]*; do 
+		dpkg -l $i 2>/dev/null | grep ^ii | awk {'print $2'} | grep [0-9] | sort | head -n -${keep}; 
+	done 
+)

update_ip.sh

@@ -0,0 +1,34 @@
+#!/bin/sh
+
+cache=.update_ip.cache
+server=ns1.example.com
+zone=dyn.example.com
+host=desktop
+secret=""
+
+ip=$(wget -q -O - http://alma.ch/myip.cgi)
+
+if [ -z ${ip} ] || [ -z ${cache} ]; then
+	exit;
+fi      
+
+if [ -f "${HOME}/${cache}" ]; then
+	old_ip=$(cat "${HOME}/${cache}")
+fi
+
+if [ "${ip}" = "${old_ip}" ]; then
+	exit;
+else
+	rm -f "${HOME}/${cache}"
+	echo "${ip}" > "${HOME}/${cache}"
+fi
+
+cat <<EOF | nsupdate
+server ${server}
+zone ${zone}.
+key ${host}.${zone} ${secret}
+update delete ${host}.${zone}.
+update add ${host}.${zone}. 60 A $ip
+update add ${host}.${zone}. 60 TXT "Updated on $(date)"
+send
+EOF