kjh@pollux.usc.edu (Kenneth J. Hendrickson) (11/24/90)
What do you loose if you get a 2-user system? How is it crippled? Do you get root + 2 users? Do you get only 2 simultaneous logins, or only 2 users in /etc/passwd? I would probably be the only user of such a system, but the idea just scares me. Is this paranoia reasonable? -- favourite oxymorons: student athlete, honest politician, civil war Ken Hendrickson N8DGN/6 kjh@usc.edu ...!uunet!usc!pollux!kjh
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (11/26/90)
In article <28370@usc> kjh@pollux.usc.edu (Kenneth J. Hendrickson) writes: | What do you loose if you get a 2-user system? How is it crippled? | Do you get root + 2 users? Do you get only 2 simultaneous logins, or | only 2 users in /etc/passwd? I would probably be the only user of such | a system, but the idea just scares me. Is this paranoia reasonable? Very! Most two user systems limit the number of user logins to two (wouldn't and reasonable implementation?), while SCO limits the gettys. So if you want to use the console and ethernet, and two serial modems, you can't, have a getty on all of them, even if you are only going to use max two at a time. SCO says they're going to look at this, but I don't know of a committment to change it. Other vendors count all console logins as one, and allow one other. For a personal system there's no problem, you can have a getty on a serial port for uucp or friends with any of the systems. And all the users in passwd you're filespace will hold. -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
dawes@suphys.physics.su.OZ.AU (David Dawes) (11/26/90)
In article <2391@sixhub.UUCP> davidsen@sixhub.UUCP (bill davidsen) writes: >In article <28370@usc> kjh@pollux.usc.edu (Kenneth J. Hendrickson) writes: >| What do you loose if you get a 2-user system? How is it crippled? >| Do you get root + 2 users? Do you get only 2 simultaneous logins, or >| only 2 users in /etc/passwd? I would probably be the only user of such >| a system, but the idea just scares me. Is this paranoia reasonable? > > Very! Most two user systems limit the number of user logins to two >(wouldn't and reasonable implementation?), while SCO limits the gettys. >So if you want to use the console and ethernet, and two serial modems, >you can't, have a getty on all of them, even if you are only going to >use max two at a time. > > SCO says they're going to look at this, but I don't know of a >committment to change it. Other vendors count all console logins as one, >and allow one other. > > For a personal system there's no problem, you can have a getty on a >serial port for uucp or friends with any of the systems. And all the >users in passwd you're filespace will hold. For what its worth: On DEC's Ultrix with a 2 user license, a max of 2 users may be logged in at a time. These 2 users may however be logged in any number of times (from ethernet, serial lines, console or wherever). root is also able to login when two other users are logged in. This to me seems the most logical way of implementing a 2-user system. David -- ------------------------------------------------------------------------------ David Dawes (dawes@suphys.physics.su.oz.au) DoD#210 | Phone: +612 692 2639 School of Physics, University of Sydney, Australia | Fax: +612 660 2903 ------------------------------------------------------------------------------
patrick@whistle.kai.com (Patrick Wolfe) (11/27/90)
>In article <28370@usc> kjh@pollux.usc.edu (Kenneth J. Hendrickson) writes: > What do you loose if you get a 2-user system? How is it crippled? > Do you get root + 2 users? Do you get only 2 simultaneous logins, or > only 2 users in /etc/passwd? Esix 3.2 Rev D allows any number of logins in the password file, but the /bin/login program stupidly restricts the number of simultaneous logins to two. I say stupidly, because it doesn't work properly. Any number of logins may be made at the console (where up to nine virtual terminals may be running), but only one login at a dialin or other port is permitted. The login program apparently counts login entries in /etc/utmp, only allowing up to one login from any port other than /dev/console or /dev/vc??. Stupid. I have a terminal in my living room, a bi-direction modem, and a two user Esix system. Now, you'd think that I'd be able to login to my terminal while someone was dialed in (as long as no one is logged into the console). Not true. Esix complains "too many users". The opposite is true too. If I'm logged into my terminal, no one can access my bbs. This problem can be worked around by replacing the "login" program. A slightly broken version of the "login" program is available from uunet.uu.net in the /unix-world directory. Be sure you don't violate your license by allowing more than two users on at one time! Patrick Wolfe Internet: patrick@whistle.kai.com UUCP: uunet!kailand!whistle!patrick
pcg@cs.aber.ac.uk (Piercarlo Grandi) (11/28/90)
On 26 Nov 90 11:30:40 GMT, dawes@suphys.physics.su.OZ.AU (David Dawes) said: dawes> Nntp-Posting-Host: suphys.physics.su.oz.au dawes> For what its worth: On DEC's Ultrix with a 2 user license, a max dawes> of 2 users may be logged in at a time. These 2 users may however dawes> be logged in any number of times (from ethernet, serial lines, dawes> console or wherever). root is also able to login when two other dawes> users are logged in. This to me seems the most logical way of dawes> implementing a 2-user system. No, it's a famous and catastrophic bug of some old release of Ultrix. It is catastrophic because the limit is not two logins, but two UIDs, as you say; so it can be easily circumvented by using the same uid for multiple users, and more nastily, if you have something like uucp or the printer spooler or other daemon running under its own UID, the number od UIDs is reduced even if nobody is logged in. -- Piercarlo Grandi | ARPA: pcg%uk.ac.aber.cs@nsfnet-relay.ac.uk Dept of CS, UCW Aberystwyth | UUCP: ...!mcsun!ukc!aber-cs!pcg Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (11/28/90)
In article <1990Nov26.113040.1865@metro.ucc.su.OZ.AU> dawes@suphys.physics.su.OZ.AU (David Dawes) writes: | For what its worth: On DEC's Ultrix with a 2 user license, a max of 2 users | may be logged in at a time. These 2 users may however be logged in any | number of times (from ethernet, serial lines, console or wherever). | root is also able to login when two other users are logged in. This to | me seems the most logical way of implementing a 2-user system. If I were AT&T I would not feel that this enforced the 2 user limit. What you seems to say (I may misread you) is that I can have 40 users on at once, as long as I have them all sign in under one login and then su to their own account. I don't want the 2 user limit to disallow any combination of two users, but I surely don't expect any freshman to be able to defeat the limit without thinking about it either. -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
dawes@suphys.physics.su.OZ.AU (David Dawes) (11/29/90)
In article <2434@sixhub.UUCP> davidsen@sixhub.UUCP (bill davidsen) writes: >In article <1990Nov26.113040.1865@metro.ucc.su.OZ.AU> dawes@suphys.physics.su.OZ.AU (David Dawes) writes: > >| For what its worth: On DEC's Ultrix with a 2 user license, a max of 2 users >| may be logged in at a time. These 2 users may however be logged in any >| number of times (from ethernet, serial lines, console or wherever). >| root is also able to login when two other users are logged in. This to >| me seems the most logical way of implementing a 2-user system. > > If I were AT&T I would not feel that this enforced the 2 user limit. >What you seems to say (I may misread you) is that I can have 40 users on >at once, as long as I have them all sign in under one login and then su >to their own account. > > I don't want the 2 user limit to disallow any combination of two >users, but I surely don't expect any freshman to be able to defeat the >limit without thinking about it either. I think I tried that, but it can't be done (unless all the users login initially as root). David -- ------------------------------------------------------------------------------ David Dawes (dawes@suphys.physics.su.oz.au) DoD#210 | Phone: +612 692 2639 School of Physics, University of Sydney, Australia | Fax: +612 660 2903 ------------------------------------------------------------------------------
aris@tabbs.UUCP (Aris Stathakis) (11/29/90)
In <2391@sixhub.UUCP> davidsen@sixhub.UUCP (Wm E. Davidsen Jr) writes: > Very! Most two user systems limit the number of user logins to two >(wouldn't and reasonable implementation?), while SCO limits the gettys. >So if you want to use the console and ethernet, and two serial modems, >you can't, have a getty on all of them, even if you are only going to >use max two at a time. > SCO says they're going to look at this, but I don't know of a >committment to change it. Other vendors count all console logins as one, >and allow one other. I disagree. SCO UNIX and OpenDesktop "2 user" versions are actually "2 Keyboard" versions. This means that you can have unlimited console logins (I'd like to see multiple users use the multi-screens at the same time :-) and one additional login (modem, ethernet, or terminal). In the case of OpenDesktop you can add an X-terminal as your second "keyboard". > For a personal system there's no problem, you can have a getty on a >serial port for uucp or friends with any of the systems. And all the >users in passwd you're filespace will hold. Sure, and it's nice for development too. Aris -- Aris Stathakis | Bang: ..!uunet!ddsw1!olsa99!tabbs!aris or aris@tabbs.UUCP - - - Disco is to music what Etch-A-Sketch is to art. -
dawes@suphys.physics.su.OZ.AU (David Dawes) (11/29/90)
In article <PCG.90Nov27172113@odin.cs.aber.ac.uk> pcg@cs.aber.ac.uk (Piercarlo Grandi) writes: >On 26 Nov 90 11:30:40 GMT, dawes@suphys.physics.su.OZ.AU (David Dawes) said: >dawes> Nntp-Posting-Host: suphys.physics.su.oz.au > >dawes> For what its worth: On DEC's Ultrix with a 2 user license, a max >dawes> of 2 users may be logged in at a time. These 2 users may however >dawes> be logged in any number of times (from ethernet, serial lines, >dawes> console or wherever). root is also able to login when two other >dawes> users are logged in. This to me seems the most logical way of >dawes> implementing a 2-user system. > >No, it's a famous and catastrophic bug of some old release of Ultrix. >It is catastrophic because the limit is not two logins, but two UIDs, as >you say; so it can be easily circumvented by using the same uid for >multiple users, and more nastily, if you have something like uucp or the >printer spooler or other daemon running under its own UID, the number od >UIDs is reduced even if nobody is logged in. As I recall, with Ultrix 2.2, the limit was two UIDs logged in. It worked on entries in /etc/utmp. Sure this can be overcome by people sharing UIDs, but (at least with this version of Ultrix) the number of UIDs was not reduced by any background or daemon processes that might be running. David -- ------------------------------------------------------------------------------ David Dawes (dawes@suphys.physics.su.oz.au) DoD#210 | Phone: +612 692 2639 School of Physics, University of Sydney, Australia | Fax: +612 660 2903 ------------------------------------------------------------------------------
det@hawkmoon.MN.ORG (Derek E. Terveer) (11/30/90)
patrick@whistle.kai.com (Patrick Wolfe) writes: >Any number of logins >may be made at the console (where up to nine virtual terminals may be running), >but only one login at a dialin or other port is permitted. The login program >apparently counts login entries in /etc/utmp, only allowing up to one login >from any port other than /dev/console or /dev/vc??. Stupid. I wonder. What if you simply renamed your tty/cul ports to be /dev/vc??. That might cut down somewhat on the number of virtual consoles, but if login just looks at the device name, how would it know that /dev/vc08 is really the name (renamed) of the modem port? derek -- Derek Terveer det@hawkmoon.MN.ORG Minnesota Field Hockey Association, North Central Section University of Minnesota Women's Lacrosse, Midwest District
ilan343@violet.berkeley.edu (Geraldo Veiga) (11/30/90)
A general question on the subject. What are the SysV 4.0 vendors doing about limited-user licences? As I remember, AT&T had revamped the licencing structure for 4.0, and limited-user = 4 users (not 2). True? Geraldo
carroll@cs.uiuc.edu (Alan M. Carroll) (12/01/90)
In article <1990Nov29.191237.22576@agate.berkeley.edu>, ilan343@violet.berkeley.edu (Geraldo Veiga) writes: > As I remember, AT&T had revamped the licencing structure for 4.0, and > limited-user = 4 users (not 2). True? We are running Intel SysV R4, limited users, and it is limited to 2 uid's. -- Alan M. Carroll "It's psychosomatic. You need a lobotomy, Epoch Development Team I'll get a saw." CS Grad / U of Ill @ Urbana ...{ucbvax,pur-ee,convex}!cs.uiuc.edu!carroll