Tweaking the CH3WNAS Power Off

On the CH3WNAS, you have to press the power button for an endless 10s before it finally shuts down. Apparently this 10s delay is determined by the /usr/sbin/chkbutton daemon that polls the power button. There exists a replacement for this process for the dsm-g600 in http://forum.dsmg600.info/t955-chkbutton-replacement.html.
Unfortunately, I couldn't download the attachment to try it out on the CH3WNAS. I asked the author to resubmit his binaries. Maybe for a next post...

There is also shutdown-option in the web-admin pages. After logon, the shutdown is done by firing a POST /goform/sysShootDown request onto the CH3WNAS. After some searching in the sourcecode (download it from the conceptronics' site), I found out that CH3WNAS_GPL/goahead/LINUX/web_api.c handles the shutdown:
void sysShootDown(webs_t wp, char_t *path, char_t *query)
if( checkIdleTime(wp) == WEB_IDLE_TIMEOUT )
websRedirect(wp, T("web/login.asp"));
system("touch /tmp/shutdown");
websRedirect(wp, T("web/tools/shutdown.asp"));
--> A simple (but unconventional) touch /tmp/shutdown triggers the shutdown. I suppose it's the same chkbutton daemon process that monitors and picks up the /tmp/shutdown file.

If you need to do a fast remote shutdown, you can exercise the existing web-interface from command line (the wget is standard under linux; under windows, have a look at wget for windows):
wget -o /tmp/test ""
wget -o /tmp/test2 ""
Replace the ip & password according to your local setup. Put those commands in a script and you get a simple way to shutdown the unit remotely with a simple double-click. The problem with this code is that you have to put your admin-password in cleartext on your pc. I haven't figured out yet how to circumvent the logon page to remove this security-issue.

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