arpwatch does not start properly on system boot, but immediately exits (legacy SysVinit-script, no systemd unit file).

[Ansgar Bohmann]

Immediately after the installation of arpwatch from the repositories it works as expected. I expected it to also work after reboot.

However, after the reboot there is no arpwatch process running and I don't receive any messages. Manually restarting it (sudo systemctl restart arpwatch) works. From the log-files I conclude that arpwatch is started too early during system boot process and immediately exits, since the network is not ready yet.

It should be noted that a legacy init script (/etc/init.d/arpwatch) is responsible for starting arpwatch. There doesn't seem to be any systemd unit file.

I'm on Xubuntu 16.10 (Yakkety Yak), 64 bit.
arpwatch version is: 2.1a15-2.

Here's the essence of what I tried:

$ ps -A | grep arp
$ systemctl --all | grep arp
arpwatch.service loaded active exited LSB: arpwatch daemon
$ journalctl | grep arpwatch
Jan 09 18:18:28 XXXXXXX systemd[1]: Starting LSB: arpwatch daemon...
Jan 09 18:18:29 XXXXXXX arpwatch[1663]: bad interface eth0: eth0: no IPv4 address assigned - assuming unconfigured interface
Jan 09 18:18:29 XXXXXXX arpwatch[1693]: pcap open eth0: eth0: That device is not up
Jan 09 18:18:29 XXXXXXX arpwatch[1570]: Starting Ethernet/FDDI station monitor daemon: (chown arpwatch /var/lib/arpwatch/eth0.dat) arpwatch-eth0.
Jan 09 18:18:29 XXXXXXX arpwatch[1747]: bad interface wlan0: wlan0: no IPv4 address assigned - assuming unconfigured interface
Jan 09 18:18:29 XXXXXXX arpwatch[1570]: Starting Ethernet/FDDI station monitor daemon: (chown arpwatch /var/lib/arpwatch/wlan0.dat) arpwatch-wlan0.
Jan 09 18:18:29 XXXXXXX systemd[1]: Started LSB: arpwatch daemon.
Jan 09 18:18:29 XXXXXXX audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=arpwatch comm="systemd" exe="/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Jan 09 18:18:29 XXXXXXX arpwatch[1748]: pcap open wlan0: wlan0: That device is not up
$ sudo systemctl start arpwatch
$ ps -A | grep arp
$ sudo systemctl restart arpwatch
$ ps -A | grep arp
 9484 ? 00:00:00 arpwatch
$

I found two possibly related reports for Rasbian and Debian:
https://raspberrypi.stackexchange.com/questions/59225/arpwatch-fails-to-autostart
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=782057

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.