4. User Management ( Real Time)

4. User Management

# id      (find out the user id information)

# dispuid        

# dispgid

# logins

# cat /etc/default/fs

Local = ufs

#listusers         (show no.of users)

Note: for user, there should be ‘home directory’.

Issues in user management:

ü  User permission

ü  User home directory missing

ü  Change the ownership (chown)

ü  Assign the permission (chmod)

ü  User missing in shadow file (pwconv)

User environment variable:

1. local.cshrc
2. local.login
3. local.profile

All file exists in /etc/skel file

# logins –l raj

How to assign groupid to user?

# groupadd unix

#usermod –g unix raj  (-g : primary group name)

# logins –l raj

#id –a raj

# usermod –G dba,dwh raj

Note: if not specifying anything to create user, it means it stored in /home

To find defadduser:

# find / -name defadduser  -print

# login –xl pra

$ ls –ltr

raj

$exit

Changing the owner ship: before it was raj, now I am changing as root

#chown root:other /sai/raj/aa

# ls –l /sai/raj/aa

#chown root:dba /sai/raj/aa

# groups

# dispgid

# cat /etc/group

Sol:143:-----     (3^rd one,if secondary group (-G) only it shows)

‘#userdel’ is a command to del the user but it cant delete the user home directories

#userdel –r:     command delete the home directory

To change the user name;

#usermod –l  roja raj

To change the group name:

#groupmod –n java sol

# man groupadd

# groupadd  ---

Above two, it show the options

#lf –F

#useradd –D (if it fire then only defadduser updates)

#cat /usr/sadm/defadduser

Issue1:

User entry missing in shadow

A: sync from passwd to shadow (pwconv)

# pwconv

Note: we can not sync from shadow to password.

Issue 2:

Password break

A: go to filesafe mode

# cd /a

#vi etc/shadow

    root/x/                 (remove 2^nd part i.e  x)

in system1:

# dtrace           /it trace all the system calls

In system2:

# rm     // rm commands not working

Now in system 1 it shows error message, it trace why ‘rm’ not working

#passwd –n 2 –w 3 –x 10 raj

User id creation: LDAP – secure – advance of NIS+

Configuration: implementation team take care

Note :

1. Once ticket comes for production server till 5 days no need to do anything.
2. Application & DBA both should be shutdown for rebooting the server

Issue 3: home directory missing

# useradd –u 144 –g dba –d /sai/ram –m ram

# usermod –d /opt/ram –m ram           (b4 ram was in sai)

# cd /opt

# ls

ram (now in /opt from /sai, in /sai not there)

issue 4: chage the ownership

# ls –ld /opt/ram

I want to change the owner ship from ram to raj

#ls –ltr

Ram dba

I want raj to access ram

#chown raj:dba /opt/ram/aa

#ls –ld /opt/ram/aa

Issue 5: only one user not loging in

ü  Check the permissions

ü  Check out the password, user

ü  Check password status, grep | username

Issue 6: one user not accessing other file

ü  Check user permissions

ü  File level permissions

Note: its not day to day activity depends on requirement

Issue 7:not a single user login to server

Then it is a server problem

Issue 8: if shadow file missing

A: sync

#pwconv

Issue 9: if passwd/opasswd file missing

A: Reconstruct