@{$data{$ip}}{@field_names} = [$fields];

##</code><code>##

@{$data{$ip}}{@field_names} = @$fields;

##</code><code>##

my $fields = [@cname, @ports, @banners];

##</code><code>##

my @fields = (\@cname, \@ports, \@banners);

##</code><code>##

 my @fields = (\@cname, \@ports, \@banners);
 
 @{$data{$ip}}{@field_names} = @fields;