Home > Articles > Operating Systems, Server

This chapter is from the book

This chapter is from the book

Bulk Imports and Exports

You may find yourself in a situation where you want to dump information out of Active Directory into a flat file for searching. Or you may need to create large numbers of objects and you want to simplify your work by importing information from a flat file. A standard Windows domain controller has a couple of utilities that help with this kind of bulk object processing. First, we need to take a look at the format for exchanging LDAP information.

LDAP Data Interchange Format (LDIF)

RFC 2849, “The LDAP Data Interchange Format (LDIF)—Technical Specification” defines a standard structure for exchanging LDAP information. The following example shows the LDIF format for the attributes of the Administrator account in the Company.com domain:

dn: CN=Administrator,CN=Users,DC=company,DC=com
memberOf: CN=Group Policy Admins,CN=Users,DC=company,DC=com
memberOf: CN=Enterprise Admins,CN=Users,DC=company,DC=com
memberOf: CN=Schema Admins,CN=Users,DC=company,DC=com
memberOf: CN=Administrators,CN=Builtin,DC=company,DC=com
memberOf: CN=Domain Admins,CN=Users,DC=company,DC=com
accountExpires: 9223372036854775807
adminCount: 1
badPasswordTime: 125693193676075896
badPwdCount: 0
codePage: 0
cn: Administrator
countryCode: 0
description: Built-in account for administering the computer/domain
isCriticalSystemObject: TRUE
lastLogoff: 0
lastLogon: 125693891796993128
logonCount: 109
distinguishedName: CN=Administrator,CN=Users,DC=company,DC=com
objectCategory: CN=Person,CN=Schema,CN=Configuration,DC=company,DC=com
objectClass: user
objectGUID:: gLgtb/ju0hGcKADAT1NqTQ==
primaryGroupID: 513
pwdLastSet: 125681556744344992
name: Administrator
sAMAccountName: Administrator
sAMAccountType: 805306368
userAccountControl: 66048
uSNChanged: 1532
uSNCreated: 1410
whenChanged: 19990410040835.0Z
whenCreated: 19990410034956.0Z

There are a few items of note with this example:

  • LDIF files use simple ASCII characters. If you have high-order Unicode values in some of the attributes, they might not survive the translation.

  • Long integers that represent time and dates will be represented in decimal format and, as such, will not survive reimport. These items are discarded and created afresh when an entry is imported and a new object created.

  • Octet strings are converted to Base64 format. This is indicated by a double-colon after the attribute name. ObjectGUID is an example. These values withstand a reimport. For the most part, though, this syntax is used for values that are unique for an object so the imported values would be ignored.

  • The attributes conform to the Active Directory schema for the forest where they were obtained. Attempting to import these values into a foreign directory service can result in compatibility issues. At the very least, you'll need to change the distinguished names, because it is unlikely that the foreign directory service would use the same namespace.

The LDIF standard includes several command verbs that are used to determine what to do with a particular record. These verbs permit adding, modifying, replacing, or deleting an entire object or individual attributes of an object. They also permit modifying the directory schema. Active Directory permits LDIF to add and modify object classes and attributes, but it does not permit them be deleted. After a class or attribute has been added to the schema, it's there to stay.

LDIF and Active Directory Schema Upgrades

Lest you think that LDIF is one of those obscure programmer toys that reasonable system administrators should avoid like it was oozing with plague, consider this: When you upgrade the first Windows 2000 domain controller in a domain to Windows Server 2003, new objects are added and old objects modified to support changes in the new operating system version. In addition, the Active Directory schema must be modified to support the new features in Windows Server 2003. How does Microsoft install these schema updates? With LDIF files, that's how.

Check the Windows Server 2003 CD in the \I386 folder. Look for a series of files with an LDF extension. These contain the LDIF entries that modify Active Directory contents and the schema. The CD includes an uncompressed executable called Schupgr.exe. This executable loads the changes from the LDF files into Active Directory.

One last feature of this upgrade method is important to note. The last step in each LDF file modifies an attribute of the Schema container called ObjectVersion. This is how Windows keeps track of the LDF files applied by Windows updates. Installing Windows Server 2003 upgrades the schema to version number 30. Installing Exchange also modifies the schema but does not change the schema version number.


A Windows domain controller comes with a command-line tool for importing and exporting LDIF files, LDIFDE. Run ldifde with no switches to get a list of parameters.

LDIFDE simplifies importing and exporting large numbers of records to and from Active Directory, but it also comes in handy for making quick checks of directory entries without opening up a pesky MMC snap-in. Use the –f con switch to direct the output to the console. For example:

  • To know the group membership of a user, use Ldifde –d cn=username,cn=Users, dc=company,dc=com –f con.

  • To check the entries in a trusted domain, use Ldifde –s alb-dc-01.office.company.com –d dc=Office,dc=Company,dc=com –f con.

  • To find all the printers in an organizational unit, use Ldifde –d ou=Phoenix, dc=Company,dc=com –r "(objectclass=printers)" –f con.

You can use LDIFDE to dump a file of information about a user and then modify the settings and the username and import that file as a new user. To do this, use the -m option to remove the SAM-specific information from the dump file.

You can also use LDIFDE to modify attributes of existing objects, but you need to know a little trick. After you've created an LDIF file consisting of entries you want to modify, you must put a dash on the first blank line at the end of the entries and then a blank line after that. Here's an example showing how to change the Description attribute for a user named Avguser:

dn: CN=avguser,OU=Phoenix,DC=company,DC=com
changetype: modify
replace: Description
Description: Wazula

Without that dash, you'll get an error similar to the following:

Failed on line 4.  The last token starts with 'W'. The change-modify entry is
missing the terminator '-'.


Working with the LDIF format can get a little tedious because it sorts attributes vertically rather than horizontally. If you prefer a more standard spreadsheet layout, use the CSVDE utility. The switches for CSVDE are the same as for LDIFDE.

Here's an example of using CSVDE. Let's say you are the administrator for a school district and you want to add 5000 new students into Active Directory. Your student list may be in a mainframe or AS400 application or a UNIX application of one form or another or a SQL database. You can write a little JCL (Job Control Language) routine or do a quick SQL query to output the student list to a delimited file. Import the delimited file into a spreadsheet and massage it until you get the required data for Active Directory. (Do a csvde -f output.ldf to see the column headings and data types.) Then use csvde -i to import the spreadsheet contents into Active Directory.

Reimporting LDIF Dumps

If you do an LDIFDE or CSVDE export, many of the attributes for user and group objects are owned by the system and cannot be reimported. Here's a trick. Run the export with the –m switch. This enables SAM Logic, which is another way of saying that the export skips the attributes that are owned by the system. This gives you a template to use when building your import files or spreadsheets.

Other LDAP Tools

Because Active Directory is an RFC-compliant implementation of LDAP, you can use virtually any LDAP tool for browsing objects and collecting information. Here are a few sources of LDAP tools and related information:

  • OpenLDAP (www.openldap.org) . If you are an open source kind of person, you should take a look at the latest wares from that community. These toolkits are not for the fainthearted, and there are no compiled packages to play with, but it's worth a peek if you want to build your own administration tools to replace those clumsy MMC snap-ins.

  • Novell (www.novell.com/products/nds/ldap.html). NetWare 5 boogies on IP and so does NDS. Novell is putting lots of calories into doing the “Internet thing” right. Also take a look at developer.novell.com for LDAP and X.500 tools that might be useful in a mixed network.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020