Where i work we have an environemnt in which many different scripts must have access to different hosts, databases etc etc. We use this method:

package Attr;

use strict;
use vars qw(%struct);

%struct =
     (
      infomgr => {
                 sid      => 'xxxxxx',
                 username => 'xxxxxx',
                 passwd   => 'xxxxxx',
                },
     )
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This way we can have multiple hosts, databases (in fact any arbitrary data.)

To reference the data in our scripts:

use Attr ();              # Application wide configuration
use vars qw(%struct);     # Grab the datastructure from the config fil
+e
*struct = \%Attr::struct; # Alias the variable out
..
..
print $self->{config}{infomgr}{sid} # for want of a better example
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We also have the OS accounts locked down tightly as well as permissions on the file. This works quite well for us as we've got a single point for all our configuration data.