SSH – Configure DBus to Allow SSH User to Suspend Server

dbusssh

I try to suspend my server using dbus and UPower. The server runs Ubuntu LucidLynx 64bit.

While everything works fine if I am sitting directly at the machine, it won't work via ssh.
If I connect to the server via ssh and try to suspend the machine using dbus and upower, it gives back

dbus.exceptions.DBusException: org.freedesktop.UPower.GeneralError: not authorized

Could anyone please tell me how to configure dbus in order to allow ssh-users to suspend the machine?

Best Answer

There are two basic ways this can be done and a workaround:

Either you need to modify /usr/share/polkit-1/actions/org.freedesktop.upower.policy, set the XDG_SESSION_COOKIE environment variable to the appropriate value or use pm-suspend:

Modifying `/usr/share/polkit-1/actions/org.freedesktop.upower.policy`

Apply this patch:

--- /usr/share/polkit-1/actions/org.freedesktop.upower.policy.orig  2011-11-16 19:06:59.274055248 +0100
+++ /usr/share/polkit-1/actions/org.freedesktop.upower.policy   2011-11-16 19:11:15.178864922 +0100
@@ -21,6 +21,7 @@
     <defaults>
       <allow_inactive>no</allow_inactive>
       <allow_active>yes</allow_active>
+      <allow_any>yes</allow_any>
     </defaults>
   </action>

(To the <action id="org.freedesktop.upower.suspend"> tag/section), and it'll work too...

`XDG_SESSION_COOKIE`

When you're using the desktop, you'll see that $XDG_SESSION_COOKIE has one value, but in an ssh session, it has another. Store XDG_SESSION_COOKIE e.g. in a .dotfile or something when the desktop starts and source it in your script that needs to do it over ssh.

pm-suspend

Or you could just give up on doing it with dbus and UPower and just issue pm-suspend as root and get it over with! :-)

Related Solutions

Ubuntu – How to suspend over ssh

Just type <enter>~& (that's three keystrokes: enter, squggle, ampersand) and ssh will go into the background, and eventually timeout by itself. That's good if you want to just abandon an interactive session in a case like this.

Or, alternatively, put that into a shell script on MyLocalPC and connect in a way that will background the connection:

ssh -f MyLocalPC go-to-sleep

SSH Server Without Static IP – How to Run SSH Server Without Static IP Address

To get started with ssh in general, install openssh-server.

sudo apt-get install openssh-server

On the next restart, this should start up automatically. To connect to the computer remotely, just enter the following in a remote terminal, substituting the ALL-CAPS names for your own:

ssh USERNAME@IPADDRESS

Now, to take care of the dynamic ip forcing you to recheck the IP all the time:

Get a free account on dyndns.com and choose the name you want to type when you connect.

Once that is done, install "ddclient" on the server machine. This will automatically update the IP address for you with dyndns.

sudo apt-get install ddclient

When you run it, it will ask you a series of questions, so have your username, password, and the URL you chose earlier ready to type in. It should also automatically add itself to startup.

That should be it. Now when you ssh, just use the URL you chose instead of your IPADDRESS since this should automatically update if the IP changes.

If you have a router, make sure to forward port 22 to your server! There are lots of guides on this at portforward.com for your specific router.