OpenLDAP Everywhere

LDAP can be seen as a tree, with foo.com at the trunk. Branches are created as organizational units (ou), as shown in Figure 2.

Each entry in the directory is uniquely identified with a distinguished name (dn). The dn for the LDAP manager looks like dn: cn=manager, dc=foo, dc=com.

The ou provides a method for grouping entries, as shown in Table 1.

Table 1. ou Method for Grouping Entries

We create the individual entries in LDIF (LDAP Interchange Format) and save them to top.ldif:

dn: dc=foo, dc=com
objectclass: dcObject
objectclass: organization
o: Foo Company
dc: foo
dn: cn=manager, dc=foo, dc=com
objectclass: organizationalRole
cn: manager
dn: ou=people, dc=foo, dc=com
ou: people
objectclass: organizationalUnit
objectclass: domainRelatedObject
associatedDomain: foo.com
dn: ou=contacts, ou=people, dc=foo, dc=com
ou: contacts
ou: people
objectclass: organizationalUnit
objectclass: domainRelatedObject
associatedDomain: foo.com
dn: ou=group, dc=foo, dc=com
ou: group
objectclass: organizationalUnit
objectclass: domainRelatedObject

Add the top-level entries to the directory with ldapadd:

ldapadd -x -D 'cn=manager,dc=foo,dc=com' -W \
-f top.ldif

Then, test your work with ldapsearch to retrieve all entries:

ldapsearch -x -b 'dc=foo,dc=com'

At this point, we have enough structure in LDAP to put it to real use. We'll start by sharing our e-mail contacts, which also should be in LDIF.

To simplify the process, you may be able to export your e-mail address book in LDIF. For example, in Mozilla 1.0, you can export in LDIF from the Tools menu on the address book window. Microsoft Outlook Express also allows exporting the address book in LDIF. You will need to process the resulting file so it looks like our contacts example below; I suggest using Perl for the task.

Contacts are uniquely identified by their e-mail addresses. Here is the dn for a sample contact:

dn: uid=someone@somewhere.com,ou=contacts,
    ou=people, dc=foo,dc=com

With all of the attributes, the full entry for a contact looks like:

dn: uid=someone@somewhere.com,ou=contacts,
    ou=people, dc=foo,dc=com
cn: Someone Youknow
mail:
uid:
givenname: Someone
sn: Youknow
objectclass: person
objectClass: top
objectClass: inetOrgPerson

Separate each contact entry with a blank line, and save it to a file called contacts.ldif. Then you can add the contacts to the directory with ldapadd:

ldapadd -x -D 'cn=manager,dc=foo,dc=com' -W \
-f contacts.ldif

Once again, test your work with an ldapsearch that retrieves all entries:

ldapsearch -x -b 'dc=foo,dc=com'

Now it's time to configure Mozilla to use the new LDAP server (see Figure 3).

From the Edit menu in the Mozilla Mail and News window, select Mail & Newsgroup Account Setting. In the Addressing tab, select Use a different LDAP server, then select Edit Directories and then Add. Fill in the Directory Server Properties dialog with:

Name: FOO
Server: ldapserver.foo.com
base DN: ou=people,dc=foo,dc=com

Next, tell Mozilla to look up addresses in your directory. Under Addressing in the Mail and Newsgroups preferences, select Address Autocompletion and fill in FOO for Directory Server.

Test your settings by composing a message to one of your contacts in your LDAP directory. The address should autocomplete as you type. Another test is to search the LDAP directory from within the Mozilla Mail Address Book. A search for Name or E-mail that contains * should return all of the contact entries. Similarly, you can also configure Microsoft Outlook Express to use the LDAP directory.