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@paul-chambers
Last active January 12, 2023 05:45
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/etc/dhcp/dhclient-enter-hooks.d
Some custom Scripts to update things that depend on the WAN IP address
#
# This script is meant to be called by dhclient from /etc/dhcp/dhclient-enter-hooks.d/
#
# It writes a config file for dnsmasq to injest for settings that are wan/isp-specific
#
# Tips:
# * Be careful about changing the environment since this is sourced
# * This script fragment uses bash features
#
_dest="/etc/dnsmasq.d/isp.conf"
case "${reason}" in
BOUND|RENEW|REBIND|REBOOT)
_lan_ip=$(ip addr show dev lanbr | sed -n -e '1,5 s/ *inet \([0-9\.]*\).*/\1/ p')
echo "# Do Not Edit - automatically generated\n" > "${_dest}"
echo "alias=${new_ip_address},${_lan_ip}\n" >> "${_dest}"
_isp_domains=$( expr match "${new_domain_name}" ".*\.\([^\.]*\.[^\.]*\)\." )
case "${_isp_domains}" in
"comcast.net")
_isp_domains="comcast.net comcast.com xfinity.net xfinity.com"
;;
esac
for _isp_domain in ${_isp_domains}
do
for _dns_ip in ${new_domain_name_servers}
do
echo "server=/${_isp_domain}/${_dns_ip}" >> "${_dest}"
done
unset _dns_ip
echo "ipset=/${_isp_domain}/isp,isp6\n" >> "${_dest}"
done
unset _isp_domain
unset _isp_domains
unset _lan_ip
systemctl restart dnsmasq.service
;;
esac
unset _dest
#
# This script is meant to be called from the /etc/dhcp/dhclient-enter-hooks.d/
#
# It prods inadyn, if it's installed, to update public IP just assigned in the
# dynamic DNS service(s) that inadyn is configured to upate.
#
# Tips:
# * Be careful about changing the environment since this is sourced
# * This script fragment uses bash features
#
case "$reason" in
BOUND|RENEW|REBIND|REBOOT)
/usr/sbin/inadyn --once --foreground --syslog
;;
esac
#
# This script is meant to be called from the /etc/dhcp/dhclient-enter-hooks.d/
# It updates a set of aliases with the first few hops as reported by traceroute
# so that they can be included in your smokeping configuration, but will be
# updated when the DHCP lease changes.
#
# Tips:
# * Be careful about changing the environment since this is sourced
# * This script fragment uses bash features
#
logger "dhclient script: ${reason} ${new_ip_address}"
destination="/var/lib/smokeping/firsthops.inc"
case "$reason" in
BOUND|RENEW|REBIND|REBOOT)
gateway=$(ip route list | sed -n -e 's/default via \([0-9\.]*\) dev \(.*\)/\1/p')
echo "@define gateway ${gateway}" > "${destination}"
counter=1
for hop in $(/usr/sbin/traceroute -m 4 -n 8.8.8.8 | /usr/bin/sed -n -e '2,5 s/ *[0-9] *\([0-9.]*\) .*$/\1/ p')
do
echo "@define hop-${counter} ${hop}"
counter=$((counter+1))
done >> "${destination}"
;;
esac
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