The docs say that the second object passed to the callback for a search will be an entry found:

If the request is a search then multiple packets can be received from the server. Each entry is received as a separate packet. For each of these the subroutine will be called with a Net::LDAP::Entry object as the second argument.

So I think the callback should look like this:

sub callback {
    my ($searchobj, $entry) = @_; # note: no 'shift'
    if ($entry) {
        print $entry->dn, "\n";
        print $entry->get_value('plan');
        print $entry->get_value('ipaddress');
        print $entry->get_value('username');
    }
    else {
        warn "No entry passed in for callback...\n";
    }
}
[download]

This will at least let you know that your callback is being called the appropriate number of times.

Chris
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