What is an LDIF File?Directory

An LDIF file is a plain-text file in the LDAP Data Interchange Format, using the .ldif extension. It carries directory information, the sort of records a directory server holds about people, groups and devices, written out in a readable, portable form. Defined in the RFC 2849 standard, it lets that data be exported, backed up and moved between directory servers, even ones from different vendors. Because it is just text, an LDIF file can be created, read and edited without special software.

LDIF stands for LDAP Data Interchange Format. LDAP is the Lightweight Directory Access Protocol, the common way software reads and writes a directory, and interchange format signals its purpose, moving that directory data between systems. The name is often said aloud as el-diff. It captures exactly what the format does, giving LDAP directory information a standard text representation that any compliant directory server can produce and consume.

An LDIF file is a list of records, one per directory entry, separated by blank lines. Each record starts with a dn line, the distinguished name, which is the entry's full address in the directory tree. Below it come the entry's details as attribute and value pairs, such as a name, surname or email address. An attribute can appear more than once to hold several values, and a double colon marks a value that has been encoded, which is how binary data like a photo travels inside the text.

An LDIF file is one of two kinds, and never both. A content file lists directory entries as they are, a snapshot suited to exporting, backing up or loading a directory fresh. A change file lists instructions instead, each record carrying a change type that says whether to add, delete or modify an entry. So a content file describes what a directory contains, while a change file describes what to do to it. Knowing which kind you have tells you what the file is for.

A DN, or distinguished name, is the unique address of an entry within a directory tree, and it begins every record in an LDIF file. It reads as a path built from parts, such as a common name followed by an organisational unit and the domain, which together pinpoint exactly one entry. Because a directory is arranged as a tree, the DN shows both who the entry is and where it sits. No two entries in a directory share the same distinguished name.

Importing means loading the file's entries into a directory server, and the tool depends on the system. On open-source directories, the OpenLDAP utilities add entries or apply changes from a file, while a matching search command exports entries back out as LDIF. On Windows, Active Directory provides its own utility to import and export directory objects as LDIF. Whichever you use, the file must match the directory's rules, so its entries and attributes have to fit the directory's schema.

Yes. Since an LDIF file is plain text, any editor can open and change it, which is one of the format's strengths. The catch is that the layout is strict, so records are separated by blank lines, spacing at the start of lines matters, and encoded values must stay intact. A small slip, such as a missing blank line, can make an import fail. So editing is fine, but it pays to keep the structure exact and to save the file as plain UTF-8 text.

The usual cause is a formatting problem, since the format is strict about layout. A missing blank line between records, an unexpected space, or a broken encoded value can stop an import partway through. Another common cause is a clash with the directory, where an entry being added already exists, or an attribute is not allowed by the directory's schema. Checking that the file's spacing is exact and that its entries fit the target directory usually clears the problem.

No, though both are plain text and both can carry directory or contact data. A CSV file is a simple table of rows and columns, flat and without structure. An LDIF file is built around the directory's tree, where each entry has a distinguished name and can carry repeating attributes and encoded values that a flat table cannot express. Directories often export to both, but LDIF preserves the full directory structure, while CSV is simpler and more limited.

A change record carries a change type that names the operation, and there are a few of them. An add creates a new entry, a delete removes one, a modify edits the attributes of an existing entry, and a modrdn renames or moves an entry. The modify type is the most detailed, since inside it you list each edit as an add, replace or delete of a single attribute, separating those edits with a line that holds only a dash. The change type is what marks a record as a change rather than plain content.

Line folding is how LDIF wraps a value that is too long for one line. You break the line and begin the continuation with a single leading space, and when the parser sees that space at the start of a line it joins the text back onto the line before, then discards the space. It lets long values stay readable without changing their meaning. The catch is that the space must be exactly one and in the right place, so an accidental space at the start of a line can join text that was meant to stand apart.

Both are built-in Windows tools for bulk directory work, but they differ in reach. The LDIF tool reads and writes LDIF files and can add, modify, delete and rename directory objects, and it can even change the directory schema. The comma-separated tool works with CSV files and can only add or export objects, so it cannot modify or delete what is already there. When you need to change or remove existing entries, or touch the schema, the LDIF tool is the one to reach for.