Apache HTTP Server Version 1.3
Manual Page: dbmmanage
dbmmanage - Create and update user authentication files in
dbmmanage filename [ command ] [ username [ encpasswd ] ]
dbmmanage is used to create and update the DBM format files
used to store usernames and password for basic authentica-
tion of HTTP users. Resources available from the httpd
Apache web server can be restricted to just the users listed
in the files created by dbmmanage. This program can only be
used when the usernames are stored in a DBM file. To use a
flat-file database see htpasswd.
This manual page only lists the command line arguments. For
details of the directives necessary to configure user
authentication in httpd see the Apache manual, which is part
of the Apache distribution or can be found at
The filename of the DBM format file. Usually without
the extension .db, .pag, or .dir.
This selects the operation to perform:
add Adds an entry for username to filename using the
encrypted password encpassword.
adduser Asks for a password and then adds an entry for
username to filename .
check Asks for a password and then checks if username
is in filename and if it's password matches the
delete Deletes the username entry from filename.
import Reads username:password entries (one per line)
from STDIN and adds them to filename. The pass-
words already has to be crypted.
update Same as the "adduser" command, except that it
makes sure username already exists in filename.
view Just displays the complete contents of the DBM
username The user for which the update operation is per-
One should be aware that there are a number of different DBM
file formats in existence, and with all likelihood,
libraries for more than one format may exist on your system.
The three primary examples are NDBM, the GNU project's GDBM,
and Berkeley DB 2. Unfortunately, all these libraries use
different file formats, and you must make sure that the file
format used by filename is the same format that dbmmanage
expects to see. dbmmanage currently has no way of determin-
ing what type of DBM file it is looking at. If used against
the wrong format, will simply return nothing, or may create
a different DBM file with a different name, or at worst, it
may corrupt the DBM file if you were attempting to write to
dbmmanage has a list of DBM format preferences, defined by
the @AnyDBM::ISA array near the beginning of the program.
Since we prefer the Berkeley DB 2 file format, the order in
which dbmmanage will look for system libraries is Berkeley
DB 2, then NDBM, and then GDBM. The first library found
will be the library dbmmanage will attempt to use for all
DBM file transactions. This ordering is slightly different
than the standard @AnyDBM::ISA ordering in perl, as well as
the ordering used by the simple dbmopen() call in Perl, so
if you use any other utilities to manage your DBM files,
they must also follow this preference ordering. Similar
care must be taken if using programs in other languages,
like C, to access these files.
Apache's mod_auth_db.c module corresponds to Berkeley DB 2
library, while mod_auth_dbm.c corresponds to the NDBM
library. Also, one can usually use the file program sup-
plied with most Unix systems to see what format a DBM file
Apache HTTP Server Version 1.3