I use a similiar system on my side, but I expanded it too also check for "ws" in the who output (all my workstations names start with ws).
In other words, no multiple logins on remote workstations, but multiple logins on the server are allowed, firstly because only a power user knows how to do it anyway, and secondly since it may be done for a good reason, e.g. a server crash, root desktop frozen, user wishes to use gnome-system-monitor to kill the offending app, crtl-alt-f2, startx -- :1 Blah blah, you get the picture :) Ciao A.J. On Wed, 2004-06-16 at 21:45, Dag Sverre Seljebotn wrote: > > i would just like to ask advise if its possible to ensure that a > > particular user can only have a single session at a time > > e.g. user1 is logged in workstation 1 therefore he isnt allowed to log > > in to workstation2 > > This might not be the solution you're looking for as it is just some > home-brewed scripting (off the top of my head, I don't have access to an LTSP > system for testing until in a week or so). There might be an easier way, I > don't know. > > NB! Before doing this make absolutely sure that you have a non-graphical way > of logging yourself in as root (either by SSH from a standalone computer (not > LTSP terminal, unless you use the special SSH runlevels) or by physical > access to server). If you accidentally block off any graphical login (which > is actually quite likely, all you need is a syntax error in the script), you > need a way to correct it. > > Basically we insert our own custom script into the Xsession startup scripts. > This means that logging in _graphically_ through X is restricted (only > allowed once, until you're completely logged out again), however logging in > through other means (getting a console from the desktop system, telnet or > SSH, etc.) is accepted, this is probably what you want. > > In Debian at least (probably in others too), inserting a graphical session > startup script is easy. In /etc/X11/Xsession.d/ there is a bunch of scripts > that are run in the order they are numbered by on X startup. Simply drop in a > new file called "10prevent-multiple-logins" (if your system doesn't have > /etc/X11/xsession.d/ you will have to insert the code into your xsession > script some other way, investigate /etc/X11 and the Xsession script in the > config directory of your login manager (/etc/X11/xdm, /etc/kde3/kdm, or > wherever gdm is located)). > > # Simple script for disallowing starting a new graphical session > # if already logged in > > # Get how many times we are logged in > logincount=$(who | grep -c "^$(whoami)") > # If we are logged in more than the session we're in right now, log out > if [ $logincount -gt 1 ]; then > # If using KDE > kdialog --error "Sorry, your're already logged in!" > # Or if using GNOME: > gdialog --msgbox "Sorry, you're already logged in!" 30 45 > exit > fi > > And that's it. Not very secure I'm sure, the point is just to prevent casual > mulitple logins, as the poweruser capable of working around this probably > knows what he or she is doing in the first place and should be allowed... > > Note that if the user doesn't log out cleanly (like, power off without logging > out at the terminal) then he or she won't be able to log in again before the > login manager has expired the session (that's about 15 minutes with my KDM > settings). > > Hope it helps! (Some feedback on this would be nice, I have not tried it in > practice, only on my laptop, and it would be fun to know if it worked > satisfactorily). > > // Dag Sverre > > > > ------------------------------------------------------- > This SF.Net email is sponsored by The 2004 JavaOne(SM) Conference > Learn from the experts at JavaOne(SM), Sun's Worldwide Java Developer > Conference, June 28 - July 1 at the Moscone Center in San Francisco, CA > REGISTER AND SAVE! http://java.sun.com/javaone/sf Priority Code NWMGYKND > _____________________________________________________________________ > Ltsp-discuss mailing list. To un-subscribe, or change prefs, goto: > https://lists.sourceforge.net/lists/listinfo/ltsp-discuss > For additional LTSP help, try #ltsp channel on irc.freenode.net -- "You have to be on the side of the underdog. Not because he is noble, he isn't, but because he is not the overdog" Terry Pratchet. A.J. Venter DireqLearn Tech Guru www.direqlearn.org http://silentcoder.blogsite.org (personal site) http://akinimod.sf.net (FOSS Projects) http://www.direqlearn.org | http://direqlearn.net/olce (Work sites) ------------------------------------------------------- This SF.Net email is sponsored by The 2004 JavaOne(SM) Conference Learn from the experts at JavaOne(SM), Sun's Worldwide Java Developer Conference, June 28 - July 1 at the Moscone Center in San Francisco, CA REGISTER AND SAVE! http://java.sun.com/javaone/sf Priority Code NWMGYKND _____________________________________________________________________ Ltsp-discuss mailing list. To un-subscribe, or change prefs, goto: https://lists.sourceforge.net/lists/listinfo/ltsp-discuss For additional LTSP help, try #ltsp channel on irc.freenode.net
