What is an NSF file?
A file with .nsf (Notes Storage Facility) extension is a database file format used by the IBM Notes software, which was previously known as Lotus Notes. It defines the schema to store different kind of objects such like emails, appointments, documents, forms and views. All this information is contained in a single NSF file for business collaboration similar to a PST/OST file. Some of the applications that can open NSF files include IBM Lotus Notes and IBM Domino.
NSF File Format Specifications
NSF files are binary in nature and their specifications are available by Joachim Metz on Github. As per these details, an NSF file comprises of:
- File Header
- Database Header
In addition, it consists of:
- Superblock
- Bucket descriptor block
- Bitmap
- Record Relocation Vector bucket
- Summary buckets
- Non-summary buckets
NSF File Header
The NSF file header is a 6 bytes in size. It consists of:
| Offset | Size | Value | Description |
|---|---|---|---|
| 0 | 2 | 0x1a 0x00 | Signature |
| 2 | 4 | The database header size |
Database header
The NSD Database header contains the following confirmed values.
- Database Information
- Database identifier (DBID)
- Replication information
- Database information buffer flags
- Title
- Categories
- Class
- Design class (template name)
- Special note identifiers
- Padding
- Database information 2
- Database information 3
- Database information 4
- Database information 5
- Padding
- Database instance identifier (DBIID)
- Replication history