Custom Query (1145 matches)

Reported by geofft, 15 years ago.

There are a couple of problems with machines that don't have network access and try to do network login.

First, there's no clear error explaining what's wrong when the machine isn't connected and you try to log in. One possible solution to this is a PAM module that tries to access the network and displays a fatal message if it can't, although we'd have to be very sure it doesn't have any false positives. (For instance, if some but not all of the Kerberos servers go down, we shouldn't deny login.)

Second, if the machine goes offline, it's possible for an AFS access to time out and make the AFS client sad until "fs checks" is run. Other services like zhm can also become unhappy. Again, we could hack a PAM module to address this; there might be cleaner solutions. An Xsession.d script, for instance, is slightly cleaner.

aseering on testers@:

Hey,

The DebAthena computer adjacent to M12-182-4 (it doesn't have a label

and I can't log in to check) is currently sad. Its Ethernet cable was unplugged when I walked up to it. I plugged it back in, and tried to log in; the login hung while trying to render my applications bar. I killed X (ctrl-alt-bksp); the machine is now sitting at a text console.

mitchb's reply:

You didn't try rebooting it? If the network cable has been out for a length of time, a whole bunch of things on the machine are going to have noticed (among them, AFS, zhm, syslogd, aptitude, etc.), and while they may recover given time, assuming that the machine will immediately be fine upon reinserting the cable is generally not accurate.

Reported by geofft, 15 years ago.

Ubuntu doesn't start the wireless network until a user has logged in, ostensibly so that it can pick up the list of preferred networks, and if they need encryption, grab the password out of the login keyring.

This interacts poorly with debathena-login-graphical. In particular, you need the wireless LAN to be working before a user logs in, so you can authenticate their network login. If you have no local users, the machine is basically useless. This mostly affects laptops, although desktops with wireless-only connections are common in places like dorm rooms that don't have many Ethernet drops.

When I heard about this problem last fall, I wrote  http://geofft.mit.edu/p/start-network.py , a simple Python script to ask NetworkManager over D-Bus to enumerate all wireless networks on all interfaces and connect to the first one named "MIT". I haven't tested it with Ubuntu 8.10 or 9.04 -- the interfaces may well have changed. It also needs to be packaged better; two options are to run this out of an initscript at boot time, and to make this a "custom command" in the GDM greeter that you can choose from the login screen.

It would be nice if you could also specify what network to connect to. To be useful, though, this functionality probably depends on running GUI applications at the login screen, which we haven't yet figured out how to do. Maybe we can use the same setup as the Firefox kiosk mode will, and create a special local user that can only choose a wireless network to log in to (via the built-in GUI applet to do this).

Ticket #208 is also relevant for this configuration, since the wireless connection is prone to disconnecting.

Reported by geofft, 15 years ago.

The client for citrix.mit.edu should be installed on cluster machines and Firefox set up appropriately such that clicking a launcher on the website Just Works.

This is a low priority issue, previously tracked in Jira as ATN-44.