topic Re: User management in Operating System - HP-UX

User management

Pluto_2 — Thu, 28 Oct 2010 06:34:43 GMT

Hi Experts,

Could you let me know, is it possible to assign same uid to different users?

Thanks and Regards,

Rahul Kumar

Re: User management

Oviwan — Thu, 28 Oct 2010 06:39:52 GMT

no. if you want to do it for folder permission you can do it with the gid.

hth

Re: User management

Pluto_2 — Thu, 28 Oct 2010 06:53:38 GMT

Hi Experts,

But I am seeing so many users on my one server that are having same user Id.

====================================

ew3284:x:60001:29000:Evelyn Walters:/home/sadm/ew3284:/usr/bin/ksh
ww3584:x:60001:29000:William Wilson:/home/sadm/ww3584:/usr/bin/ksh
rd2197:x:60001:29000:Ronald Dunn:/home/sadm/rd2197:/usr/bin/ksh
pd2184:x:60001:29000:Phillip Dinkins:/home/sadm/pd2184:/usr/bin/ksh
ws2851:x:60001:29000:William Shelton:/home/sadm/ws2851:/usr/bin/ksh
rs7161:x:60001:29000:Robert Surber:/home/sadm/rs7161:/usr/bin/ksh
sb878q:x:60001:1229:Sudip Basnet:/home/acsisupt/sb878q:/usr/bin/ksh
qw321v:x:60001:187:Quincy Washington:/home/nbu/qw321v:/usr/bin/ksh
nv8510:x:60001:350:Neeraj Vashisht:/home/oper/nv8510:/usr/bin/ksh
ms945x:x:60001:350:Mehul Sharma:/home/oper/ms945x:/usr/bin/ksh
rr221v:x:60001:350:Rajesh Rajput:/home/oper/rr221v:/usr/bin/ksh
aa686w:x:60001:350:Ankit Aggarwal:/home/oper/aa686w:/usr/bin/ksh
pk161j:x:60001:350:Panda Kaustav:/home/oper/pk161j:/usr/bin/ksh
pg8524:x:8524:48597:Peter Gun :/home/sdbuild/pg8524:/usr/bin/ksh
sa099k:x:3915157:1229:Sukumar Arumugam:/home/acsisupt/sa099k:/usr/bin/ksh

Please suggets on this. Is it possible?

Re: User management

Kapil Jha — Thu, 28 Oct 2010 06:56:02 GMT

If two users are assigned the same UID , UNIX views them as the same user, even if they have different usernames and passwords. Two users with the same UID can freely read and delete each other's files and can kill each other's programs. Giving two users the same UID is almost always a bad idea;

BR,
Kapil+

Re: User management

Kapil Jha — Thu, 28 Oct 2010 06:56:38 GMT

Refer this link.

http://docstore.mik.ua/orelly/networking/puis/ch04_01.htm

BR,
Kapil+

Re: User management

Kapil Jha — Thu, 28 Oct 2010 06:57:55 GMT

Pluto,

You are in deep trouble my firend, you need to change the user-id,
your system is really messed up :)

clear the mess, and make user id unique for every user.

BR,
Kapil+

Re: User management

Bill Hassell — Thu, 28 Oct 2010 14:07:59 GMT

> is it possible to assign same uid to different users?

Yes, and you are seeing that already. Use the command:

logins -d

And you'll see the problem. A user name is nothing more than a symbolic name, similar to a hostname. The UID is the real ID, while the username is just an alias to the UID number.

Additionally, hackers will often hijack a username and change the UID to 0, thus ctreating a duplicate root user (a big security problem).

Re: User management

Viktor Balogh — Fri, 29 Oct 2010 08:26:40 GMT

Hi,

This is a bad config, I have encountered it already at one of our customers. The thing is that they interpreted the unix rights wrong. For this they should have used the GID. For easily changing the UID, use my performance-optimized script:

http://viktorbalogh.net/blog/languages_scripting/advanced-scripting-changing-the-uid-of-a-user

It starts parallel (findâ ¦.chown) processes to get the job done as fast as it can be.

Regards,
Viktor