Add a new user or group

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There are two separate NPG user databases to which you may wish to add a user. Unix accounts for the servers and Linux workstations are provided by LDAP on Einstein. User accounts for Mac workstations are maintained by the Open Directory (Mac LDAP) service on okra.

When creating a new account you need to first decide if it will be Linux only or if the user needs to be able to use the Mac workstations. If you're making a Mac account make sure to create a matching Linux/Unix account with the same username and uid to give the user access to servers and e-mail.

Creating Linux Accounts

There are several ways to add a new user to an OpenLDAP database. There are both GUI and console based methods (which are detailed below). Make sure when creating a new Linux accounts that home folders and mail folders for each user are stored on Gourd in /home and /mail respectively, and that you need to create these folders manually and assign the correct permissions before users will be able to access their accounts.

GUI Applications

There are a couple of graphical applications for managing LDAP databases.

  • Luma is a QT-based LDAP management application for Linux written in python. It should be available on all NPG workstations. Instructions for user management with Luma are here.
  • Jxplorer is a java based graphical application for browsing and managing LDAP databases.

Adding users from the console

It appears that the the utilities /usr/sbin/luseradd, /usr/sbin/luserdel, and /usr/sbin/lusermod are intended to allow administrators to add, delete, and modify users from the command line. Unfortunately they don't seem to work in our LDAP environment. There is alternative method to add or modify LDAP entries using the ldapadd and ldapmodify commands, but it's a bit more complex. Here's a quick overview:

In order to add or modify entries this way you'll first need an LDIF file. You can export an existing entry in the LDAP directory using the Luma browser plugin, or via the ldapsearch command. Here's the command you need to export an existing entry to an ldif file:

ldapsearch -x -L 'uid=user' > user.ldif

Here is a sample LDIF file for a user account:

dn: uid=fry,ou=People,dc=physics,dc=unh,dc=edu
uid: fry
objectClass: top
objectClass: posixAccount
objectClass: shadowAccount
objectClass: inetOrgPerson
objectClass: organizationalPerson
objectClass: person
loginShell: /bin/bash
uidNumber: 6000
gidNumber: 6000
gecos: Phillip J. Fry
sn: fry
homeDirectory: /net/home/fry
mail: PhillipJFry@planetexpress.com
cn: Philip J. Fry

You can use the following command to add the contents of this ldif file to the LDAP database. If you're logged into Einstein as root run this command:

ldapadd  -x -W -D "cn=root,dc=physics,dc=unh,dc=edu" -v -f user.ldif

NOTE: If you're running the command via sudo you need to explicitly set the home environment to root. This should do the trick:

 env HOME=/root ldapadd  -x -W -D "cn=root,dc=physics,dc=unh,dc=edu" -v -f user.ldif

Adding Groups

Luma does not provide a convenient way to create new LDAP groups. An add group option exists but it won't allow you to set a gid number above 99. If you want your new user to have a private group as their primary group (or any group that doesn't already exist) you need to create it before creating the user account. The easiest way to add a new group is using the ldapadd command with an ldif file the "hard" way

Here's a sample LDIF file that should get you a basic group:

dn: cn=newgroup,ou=Group,dc=physics,dc=unh,dc=edu
cn: newgroup
gidNumber: 6000
objectClass: posixGroup

Just change the name "newgroup" to your new group's name, and set the gidNumber to something reasonable like one above the highest currently used gid number. To quickly find out the highest gid currently in use login to Einstein and execute this command:

getent group | awk -F':' '{print $3}' | sort -n

Ignore the highest gid number (something like 4294967294). This is a system group used by NFS. Go with the one right before that, or if there is some gap in GID numbers (for example the list skips from 4039 to 4050), you can use one of those numbers to fill in those gaps.

Creating Mac Accounts

The Workgroup Manager on okra is used to add new user accounts on the Mac systems.