LDAP

1. LDAP is the Lightweight Directory Access Protocol, is an application protocol for accessing and maintaining distributed server directory information services over an TCP/IP network.
2. LDAP Servers - Netscape Directory Server, Microsoft Active Directory (AD), Novell Directory Services (NDS), Sun Directory Services (SDS), ucent's Internet Directory Server (IDS)
3. LDAP uses a client server model, with clients sending LDAP request over TCP/IP to the server.
4. Stores attribute based data information. Stores these entries in a hierachial structure (i.e., Directory Information Tree(DIT)), based on the unique identifier (Distinguish Name(DN)).
5. Designed to be read data more than written, such as No transactions or rollback.
6. LDIF - LDAP Data Interchange Format, is a human readable format, to allow easily
   exchanging and modifying of the data.
   
   ldbmcat converts ldbm database to ldif. ldif2ldbm converts ldif back to ldbm database.
   
   LDIF example, entry for a user account
   dn : CN=Day Night,CN=Users,DC=DNS,DC=local
   cn: Day Night
   objectclass: top
   objectclass: person
   objectclass: organizationalPerson
   objectclass: user
   mail : mkader@daynightsoft.com
   mailnickname : mkader
   memberof : CN=DNS-SPAdmin,CN=Users,DC=DNS,DC=local
   
7. Abbreviations
   uid - User ID
   cn - Comman Name
   sn - Surname
   l - Location
   ou - Organization Unit
   o- Organization
   dc - domain Component
   st - state
   c - country
   oid - Object Identifier
   RDN - Relative Distinuished Name
   
8. Search Filters - Criteria for attributes that must be fulfilled for an entry to be returned, and a base DN that the search is performed against
   
   Operators
   & - and
   | - or
   ! - not
   ~= - approx equal
   >= - greater than or equal
   <= - less than or equal
   * - any
   
   Example
   (&(uid=d*)(uid=*l)) - search for all users who's userid (uid), started with d and ended with l. (cn=Jim*)
9. LDAP URL - ldap://hostname:[portnumber]/[attributes][ "?" scope "?" filter]
   
   attributes - List of attributes you want returned
   scope - base = base object search, one = one level search, sub = subtree search
   filter - Standard LDAP search filter
   
   Examples:
   LDAP://DNS-FPS01.DNS.local:389/DC=DNS,DC=local
   ldap://ldap.sun.com/dc=bar,dc=com?cn?sub?uid=jim
10. LDAP Windows AD Search
    Open Active Directory Users and Computers. Right-click the domain object and select Find.
    
    Click the drop-down list next to Find, and then select Custom Search. From the next screen, select the Advanced tab. Type the appropriate LDAP statement under Enter LDAP query.
    
11. LDAP WINDOWS AD search using LDP tool
    Open LDP and connect to a valid domain controller.
    
    
    
    
    
12. LDAP command line UNIX tools
    ldapadd, ldapmodify - Used to add or modify ldap entries
    $ ldapmodify -r -D 'cn=foo,dc=bar,dc=com' -W < /tmp/user.ldif
     ldapdelete - Used to delete entries
    $ ldapdelete -D 'cn=foo,dc=bar,dc=com' -W 'cn=user,dc=bar,dc=com'
    ldapsearch - Used to search ldap servers
    $ ldapsearch -L -D 'cn=foo,dc=bar,dc=com' 'objectclass=posixAccount'