[solved] Network Manager dispatcher script ends up with zombie process

orschiro · 2013-10-30 06:37:56

Take this simple dispatcher script:

#!/bin/bash

INTERFACE=$1 # The interface which is brought up or down
STATUS=$2 # The new state of the interface

case "$STATUS" in
    up) # $INTERFACE is up        
            su -c "DISPLAY=:0 dropboxd &" orschiro
        ;;
    down) # $INTERFACE is down
        ;;
esac

All it does is to start dropbox daemon after a successful connection. The result is, however, that the dropbox tray icon appears for ~3 seconds before it disappears again.

A zombie process remains:

~ $ ps aux | grep dropbox
orschiro   779  0.0  0.0      0     0 tty1     Z    Okt29   0:23 [dropbox] <defunct>

Any idea why this is happening?

Last edited by orschiro (2013-11-04 11:44:55)

aesiris · 2013-10-30 10:59:17

Why don't you use systemd to keep track of the daemon, instead of (failing to properly) orphan it?

systemctl start dropbox@orschiro.service

orschiro · 2013-10-30 12:27:06

I used to use the systemd dispatcher but sometimes encounter that the tray icon is not showing up correctly. Thus I wanted to test it with the (old) method and see if the problem remains the same.

Strike0 · 2013-10-31 21:21:54

It happens because NM-dispatcher is for short-lived scripts and there is a 3 sec timeout, which you have witnessed in your first post. https://bugzilla.redhat.com/show_bug.cgi?id=982734

orschiro · 2013-10-31 22:42:42

@Strike0

Thanks for the report! I was never aware of that 3 seconds rule.

Is there any way for me to measure how long it takes to launch ` su -c "DISPLAY=:0 dropboxd &" orschiro`?

Then I can be certainly sure and seek for ways how to improve the script run time.

Strike0 · 2013-11-01 12:57:16

Maybe prepend "time" to the script command. But the problem may not be the script, but the dispatcher which gets 'cleaned' up after 3 secs leaving you the zombie. I had a similar problem and read somewhere that modding the dispatcher service by adding "RemainAFterExit=" might help, but still have to try that.

orschiro · 2013-11-01 14:14:37

Nice one!

I added `RemainAfterExit=Yes` to `/etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service` and so far my dispatcher script has not been killed!

I will test it a bit though before being too optimistic about it.

~ $ cat /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service 
[Unit]
Description=Network Manager Script Dispatcher Service

[Service]
Type=dbus
BusName=org.freedesktop.nm_dispatcher
ExecStart=/usr/lib/networkmanager/nm-dispatcher.action
RemainAfterExit=yes

[Install]
Alias=dbus-org.freedesktop.nm-dispatcher.service

orschiro · 2013-11-04 11:44:44

After having tested it more deeply, I can confirm that it is proven workaround.

I created a respective Wiki section for it: https://wiki.archlinux.org/index.php/Ne … ds_timeout

Arch Linux

#1 2013-10-30 06:37:56

[solved] Network Manager dispatcher script ends up with zombie process

#2 2013-10-30 10:59:17

Re: [solved] Network Manager dispatcher script ends up with zombie process

#3 2013-10-30 12:27:06

Re: [solved] Network Manager dispatcher script ends up with zombie process

#4 2013-10-31 21:21:54

Re: [solved] Network Manager dispatcher script ends up with zombie process

#5 2013-10-31 22:42:42

Re: [solved] Network Manager dispatcher script ends up with zombie process

#6 2013-11-01 12:57:16

Re: [solved] Network Manager dispatcher script ends up with zombie process

#7 2013-11-01 14:14:37

Re: [solved] Network Manager dispatcher script ends up with zombie process

#8 2013-11-04 11:44:44

Re: [solved] Network Manager dispatcher script ends up with zombie process

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