OpenSUSE to drop ZENworks [LWN.net]

Firefox phishing filter

Posted Apr 22, 2007 8:39 UTC (Sun) by hingo (guest, #14792) [Link]

This is actually a common problem with many Linux/Open Source apps: They have forgotten about the concept of dialup links. (And increasingly on Windows, the MS security update itself likes to download stuff over gprs unless it is switched to manual.) There are things that should work like this when on a network with enough bandwidth, but that should know to yield when on a dialup or slow or costly link.

Is there even a good way on Linux to check whether you are on dialup on Linux? As I understand it, in the above example Firefox just opens network sockets and the ISDN dialup software runs to serve the request and open a network connection. There should be a way to say: "I'd like to connect to google servers the next time network is up (for some other reason)."

Firefox phishing filter

Posted Apr 22, 2007 12:53 UTC (Sun) by cesarb (subscriber, #6266) [Link]

It's not possible to reliably detect a dialup/costly link, or even if the link is up, since it could be elsewhere (for instance, on a router). One solution I recall looking at long ago (back when I still used dialup) is diald; with it, you could specify which packets would bring up the link (for instance, you could make UDP packets to port 123 (ntp) never bring up the link, nor be counted as using the link for the purpose of disconnecting it due to inactivity).

profiles?

Posted Apr 22, 2007 21:30 UTC (Sun) by eru (subscriber, #2753) [Link]

Is there even a good way on Linux to check whether you are on dialup on Linux?

Or even conveniently bring up different sets of services at boot time? Eg. you would get a menu with entries like "broadband", "dialup", "a place where I have a fixed IP address N.N.N.N", "no network at all" etc. before init runs, and each could be made to start up different sets of things. (This obviously is useful only on systems normally booted with a user in attendance, like desktops and laptops).

The SysV init runlevels do not handle this, because they are rather hierarchical (level N assumes services started at level N-1 are running). In this case it is not a question of network vs no network, but different kinds of network.

I guess what I want isn't very hard to implement in principle, but it would probably be very distribution-dependent. I wonder if there is existing software like this?

already done

Posted Apr 23, 2007 5:57 UTC (Mon) by niner (subscriber, #26151) [Link]

Ironically the scolded SUSE is exactly the distribution that already has a system like you describe: the System Configuration Profile Management.

"SCPM enables your system to save different configurations in profiles. You can boot directly into a profile as well as switch profiles at run time. It is the successor of scheme management."

already done

Posted Apr 23, 2007 8:29 UTC (Mon) by macc (subscriber, #510) [Link]

Right, and I use SCPM for mobile stuff role based changes and
to switch between my home and my customers networks
for newly installed boxes or those that are in for repair/update.

My critique was about having expensive ( resourcewise ) software
installed and running by default ( and only an absolute minority
of users having any real use for that.)

YaST currently is too splintered to give access to switching
these features in a meaningfull way.

Forex adding some timesource via serial line breaks _silently_
on apparmor rules for ntpd. ( had some Talk, fixed )

The answers to my original post are up to slahdot level.

MACC

already done

Posted Apr 23, 2007 20:11 UTC (Mon) by k8to (subscriber, #15413) [Link]

I respectfully submit that you may wish to reexamine your original post then. The folks who responded do generally give useful and constructive replies.

profiles?

Posted Apr 23, 2007 12:23 UTC (Mon) by NAR (subscriber, #1313) [Link]

Well, the boot manager could pass a command line to the kernel, which would be ignored by the kernel, but the init scripts could read it from the /proc/cmdline and could do different things depending on this parameter... Our local IT staff uses a (very limited) solution like this, so the laptops have "network" and "standalone" menu items in lilo.

Bye,NAR

Kernel command line usage

Posted Apr 24, 2007 5:54 UTC (Tue) by eru (subscriber, #2753) [Link]

Interesting! I always thought the kernel command line is available only for passing options to the kernel itself. But how can I make sure that any extra 'profile' options placed on the command line are not intercepted by the kernel (not now, nor in the future when new kernel options are added)?

Kernel command line usage

Posted Apr 24, 2007 22:11 UTC (Tue) by nix (subscriber, #2304) [Link]

You, um, can't. A number of things (notably arch-dependent things) get
involved even before the initramfs runs, and can consume args as they
wish. (Adding extra arguments is *very* useful for initramfses and
initrds; arguments to mount root filesystems in unusual ways, to run
emergency repair shells just before or just after mounting root, and,
well, to trigger anything else you can think of).

However, it's quite unlikely that a random argument you pick will
name-clash, and if it does you can always rename it.

profiles?

Posted Apr 24, 2007 18:52 UTC (Tue) by JoeF (subscriber, #4486) [Link]

I use different lilo "append=" options on my Slackware bootup on my laptop. I modified the rc.* files to change things like network settings according to the option I select.