Solved: NTP and update-resolv-conf

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Pippin
Level 3
Level 3
Posts: 146
Joined: Wed Dec 13, 2017 11:14 am
Location: NL/DE/TH

Solved: NTP and update-resolv-conf

Post by Pippin » Thu Jan 18, 2018 11:19 am

Hi,

Using update-resolv-conf script I just discovered that dhcp-option NTP is not working.
tcpdump shows NTP going to the system configured server instead of the pushed one.
update-resolv-conf

Code: Select all

#!/bin/bash
# 
# Parses DHCP options from openvpn to update resolv.conf
# To use set as 'up' and 'down' script in your openvpn *.conf:
# up /etc/openvpn/update-resolv-conf
# down /etc/openvpn/update-resolv-conf
#
# Used snippets of resolvconf script by Thomas Hood and Chris Hanson.
# Licensed under the GNU GPL.  See /usr/share/common-licenses/GPL. 
# 
# Example envs set from openvpn:
#
#     foreign_option_1='dhcp-option DNS 193.43.27.132'
#     foreign_option_2='dhcp-option DNS 193.43.27.133'
#     foreign_option_3='dhcp-option DOMAIN be.bnc.ch'
#

[ -x /sbin/resolvconf ] || exit 0
[ "$script_type" ] || exit 0
[ "$dev" ] || exit 0

split_into_parts()
{
	part1="$1"
	part2="$2"
	part3="$3"
}

case "$script_type" in
  up)
	NMSRVRS=""
	SRCHS=""
	for optionvarname in ${!foreign_option_*} ; do
		option="${!optionvarname}"
		echo "$option"
		split_into_parts $option
		if [ "$part1" = "dhcp-option" ] ; then
			if [ "$part2" = "DNS" ] ; then
				NMSRVRS="${NMSRVRS:+$NMSRVRS }$part3"
			elif [ "$part2" = "DOMAIN" ] ; then
				SRCHS="${SRCHS:+$SRCHS }$part3"
			fi
		fi
	done
	R=""
	[ "$SRCHS" ] && R="search $SRCHS
"
	for NS in $NMSRVRS ; do
        	R="${R}nameserver $NS
"
	done
	echo -n "$R" | /sbin/resolvconf -a "${dev}.openvpn"
	;;
  down)
	/sbin/resolvconf -d "${dev}.openvpn"
	;;
esac
Can see that DNS and DOMAIN is done.
Since I know too little about scripting, someone willing to adjust it too include NTP?

Thanks.
Last edited by Pippin on Fri Jan 19, 2018 10:03 am, edited 1 time in total.
"One good thing about music, when it hits you feel no pain.”
B.M.

Pippin
Level 3
Level 3
Posts: 146
Joined: Wed Dec 13, 2017 11:14 am
Location: NL/DE/TH

Re: NTP and update-resolv-conf

Post by Pippin » Fri Jan 19, 2018 10:03 am

Solved using up/down script.

client.conf:

Code: Select all

setenv PATH /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
script-security 2
up /etc/openvpn/up.sh
down /etc/openvpn/down.sh
down-pre
up.sh

Code: Select all

#!/bin/sh -x

run() {
    $@
    if [ $? -ne 0 ]
        then
        echo "$@ Failed with exit code $?"
        return 1
    else
        return 0
    fi
}

run /etc/openvpn/update-resolv-conf &&
    run mv /etc/ntp.conf /etc/ntp-bak.conf &&
        mv /etc/ntp-ovpn.conf /etc/ntp.conf &&
            run systemctl restart ntp
down.sh

Code: Select all

#!/bin/sh -x

run() {
    $@
    if [ $? -ne 0 ]
        then
        echo "$@ Failed with exit code $?"
        return 1
    else
        return 0
    fi
}

run /etc/openvpn/update-resolv-conf &&
    run mv /etc/ntp.conf /etc/ntp-ovpn.conf &&
        mv /etc/ntp-bak.conf /etc/ntp.conf &&
            run systemctl restart ntp
"One good thing about music, when it hits you feel no pain.”
B.M.

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