Scaling
Configuring Database Caching of User Profiles
 
  RADIUS offers database support for caching user profiles to increase
the speed and efficiency of user lookups. It is recommends to cache user
profiles when the users  file contains more than 500 users.
  The builddbm  utility included with RADIUS for UNIX
converts the users  text file to the UNIX DBM format, which
increases the speed of user lookups.
  To run builddbm , use the following commands:
   cd /etc/raddb
  ./builddbm
- 
  RADIUS uses the new database when it receives its next authentication
request.
- 
  To run the radiusd  daemon after the users file is converted
to DBM, run radiusd  with the -b  option:
   /etc/radiusd -b
The builddbm  utility generates
users.dir 
and users.pag  files that are used by the radiusd 
daemon. On some versions of UNIX a single users.db  file is
created instead. If duplicate users  file profiles are present,
builddbm 
prints the number of profiles and identifies the line number of the duplicate
profiles.  After the users  file has been converted to the .dbm 
format, you must run builddbm  again if you make any changes to the
user profiles.
Configure  Radiusd to use PAM modules to authenticate
users by more efficient security systems.
Example of using /etc/pwd.db or /etc/spwd.db  on FreeBSD
instead of  the  f lat /etc/passwd .