my %application = (
    'CI10335478' => { 
      name => 'app_name1',
      IP   => [ 'MemberIP 1',
                'MemberIP 2',
                'MemberIP 6', ],
    },
    'CI10334984' => { 
      name => 'app_name2',
      IP   => [ 'MemberIP 4',
                'MemberIP 2', ],
    },
);

##</code><code>##


our %arx_data = ();


Need code to build HOH here...

Something like this.

        if ( $data[$class_pos] eq "cmdb_ci_appl" ) {
            my @ci_record = { description => $data[$ci_pos], name =>  $data[$name_pos] };
            push @{arx_data{ $data[$application_pos] }}, @ci_record;
            print Dumper( %arx_data ) ;
        }

        if ( $data[$application_pos] ne "" && $data[$ip_address_pos] ne "" ) {
            my @member = { description => $data[$ci_pos], name =>  $data[$name_pos] };
            $arx_data{ $data[$application_pos] }{ 'members' } = $data[$ip_address_pos];
            print Dumper( %arx_data ) ;



##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;
use 5.014;
use MIME::Base64;
use Data::Dumper;
use utf8;
use Text::Unidecode;
use XML::Twig;
use REST::Client;
use Data::Validate::Domain qw(is_hostname);
use Socket;
use Net::DNS;
use Net::MAC;
# Just in case we want to request JSON instead of XML from CMDB
#use JSON; Just in case we want to request JSON instead of XML from CMDB


my $scriptversion = "1.01 (Vance Turner, Staples Inc., 1/20/2016)";
 
our $header_count = 0;
our $fqdn_pos = 0;
our $ip_address_pos = 0;
our $dns_domain_pos = 0;
our $name_pos = 0;
our $mac_address_pos = 0;
our $application_pos = 0;
our $ci_pos = 0;
our $class_pos = 0;
our @arx_data = ();
our $arx_data_ref = \@arx_data;

# declare our command line options variables.
our $host = 'https://staplessb.service-now.com';
our $wanthelp = 0;
our $record_limit = 10;
our $class = '';
our $user = '';
our $pwd = '';
our $outputfile = '';
our $forcefile = 0;
our $verbosity = 1;

sub usage
{
    my $err = shift and select STDERR;
    print <<EOU;
usage: perl $0 [-r <max_records>] [-c <class>] [-q <quot>] [-w <width>] [-d <dtfmt>]
                        [-F] [-f] [-D <cols>] [-u] [-v <level>]
                        [-o <outputfilename>]

    -t <host_url>         use <host_url> for the CMDB connection to open. (https://staplessb.service-now.com)
    -r <record_limit>     use <record_limit> as the maximum nomber of CMDB records to retrieve, default = '100'
    -c <class>            use <class> as the CMDB class records you want to retrieve.
    -u <username>         CMDB username to use
    -p <password>         CMDB password to use
    -v <level>            verbosity, default = $verbosity, maximum = 4, written to stderr.
    -o <outputfilename>   write output to file named <outputfilename>, defaults
                          to stdout if no outputfile is specified 
    -f                    force usage of <outputfilename> if it already exists (unlink before use)

Examples:
   perl $0 -u user -p password -r max_records -o outputfile.csv   (creates outputfile.csv)
   perl $0 -u user -p password -v 4 -r max_records outputfile.csv (creates outputfile.csv, shows progress msgs)

EOU
    exit $err;
} # usage

use Getopt::Long qw(:config bundling nopermute passthrough);

GetOptions (
    "help|h|?"	=> \$wanthelp ,
    "t=s"	=> \$host,
    "r=i"	=> \$record_limit,
    "c=s"	=> \$class,
    "u=s"	=> \$user,
    "p=s"	=> \$pwd,
    "o=s"	=> \$outputfile,
    "f"		=> \$forcefile,
    "v:1"	=> \$verbosity,
    );

if ($wanthelp) {
  usage(1);
}

if ($verbosity > 1) {
   print STDERR  "\$0 script version " . $scriptversion . "\n\n";
}

if ($verbosity > 1) {
  print STDERR "Output file is   " . $outputfile . "\n";
}

-s $outputfile && $forcefile and unlink $outputfile;
if (-s $outputfile) {
    print STDERR "File '$outputfile' already exists. Overwrite? [y/N] > N\b";
    scalar <STDIN> =~ m/^[yj](es|a)?$/i or exit;
    }
 
my $client = REST::Client->new(host => $host);
 
my $encoded_auth = encode_base64("$user:$pwd", '');

$client->GET("/api/now/table/cmdb_ci?sysparm_limit=$record_limit",
                               
                {'Authorization' => "Basic $encoded_auth",
                 
                 'Accept' => 'application/xml'}); 
 
my $input_xml = $client->responseContent();

my $field= $ARGV[0] || 'u_ci_id';
my $twig = 'XML::Twig'->new;
$twig->xparse($input_xml);

my $root = $twig->root;
my @records = $root->children;

my @sorted = sort {     $b->first_child( $field)->text
                    cmp $a->first_child( $field)->text
                } @records;
 
if ($outputfile ne "") {
    open my $outputfile_fh, '>:encoding(utf8)', $outputfile or die "Cannot open: $outputfile: $!";
    close($outputfile_fh) || warn "close failed: $!";
}

my $header_printed = 0;
#for my $record (@sorted) {
for my $record (@records) {

    my @info_tags = $record->children;
    my @data;

    for my $info_tag (@info_tags) {
        my $extract = $header_printed ? 'text' : 'name';
	if ( $header_printed != 1) {
            if ( $info_tag->$extract eq 'fqdn' ) {
                $fqdn_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'ip_address' ) {
                $ip_address_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'dns_domain' ) {
                $dns_domain_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'name' ) {
                $name_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'mac_address' ) {
                $mac_address_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'u_application_id' ) {
                $application_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'u_ci_id' ) {
                $ci_pos = $header_count;
            }
            if ( $info_tag->$extract eq 'sys_class_name' ) {
                $class_pos = $header_count;
            }
        }
        my $work = $info_tag->$extract;
        $work =~ s/\r|\n//g;    	# Cleanup Carraige Returns
        $work =~ s/, / /g;		# Cleanup Comma Space
        $work =~ s/,/ /g;		# Cleanup Comma
        $work =~ s/"//g;		# Cleanup Parentheses
        $work =~ s/^\s+|\s+$//g;	# Trim spaces
        $work =~ s/([^[:ascii:]]+)/unidecode($1)/ge;
        push @data, $work;
    	$header_count++;
    }
    if ( $header_printed == 1) {
#        if ( $data[$ip_address_pos] eq "" && $data[$name_pos] ne "" && is_hostname($data[$name_pos])) {
#            my $address = inet_aton($data[$name_pos]) || "Error: Can't resolve.";
#            if ( $address ne "" && $address ne "Error: Can't resolve." ) {
#                $address = inet_ntoa($address);
#                splice @data, ($ip_address_pos), 1, $address;
#                my $cmdb_name = $data[$name_pos];
#        	my $cmdb_lc_name = lc $cmdb_name;
#                splice @data, ($name_pos), 1, $cmdb_lc_name;
#            }
#        }

#        if ( $data[$fqdn_pos] eq "" && $data[$ip_address_pos] ne "" ) {
#            my $ip_addr = inet_aton($data[$ip_address_pos]) ||  "Error: Can't resolve.";
#            if ( $ip_addr ne "" && $ip_addr ne "Error: Can't resolve." ) {
#                my $hostname = gethostbyaddr($ip_addr, AF_INET ) ||  "Error: Can't resolve.";
#	        if ( $hostname ne "" && $hostname ne "Error: Can't resolve." ) {
#                    my $lc_hostname = lc $hostname;
#                    splice @data, ($fqdn_pos), 1, $lc_hostname;
#                    my $cmdb_name = $data[$name_pos];
#                    my $cmdb_lc_name = lc $cmdb_name;
#                    splice @data, ($name_pos), 1, $cmdb_lc_name;
#                }
#            }
#        }

#        if ( $data[$mac_address_pos] ne "" ) {
#            my $mac = uc $data[$mac_address_pos];
#               $mac =~ s/\'//g;
#               $mac =~ s/\-//g;
#               $mac =~ s/\://g;
#               $mac =~ s/\"//g;
#            splice @data, ($mac_address_pos), 1, $mac;
#        }
#        if ( $data[$dns_domain_pos] eq "" && $data[$fqdn_pos] ne "" ) {
#            my $dns_domain = $data[$fqdn_pos];
#               $dns_domain =~ s/.*?\.//;
#            splice @data, ($dns_domain_pos), 1, $dns_domain;
#        }
        if ( $data[$class_pos] eq "cmdb_ci_appl" ) {
            my @ci_record = { description => $data[$ci_pos], name =>  $data[$name_pos] };
            push(@$arx_data_ref, @ci_record);
            print Dumper( @$arx_data_ref ) ;
        }

        if ( $data[$application_pos] ne "" && $data[$ip_address_pos] ne "" ) {
            my @member = { member => $data[$ip_address_pos] };
            push(@$arx_data_ref, @member);
            print Dumper( @$arx_data_ref ) ;
        }
    }
    if ($outputfile ne "") {
        open my $outputfile_fh, '>>:encoding(utf8)', $outputfile or die "Cannot open: $outputfile: $!";
        say $outputfile_fh join ',', map qq("$_"), @data;
        close($outputfile_fh) || warn "close failed: $!";
    } else {
        say join ',', map qq("$_"), @data;
    }
 
    $header_printed = 1;
    $header_count = 0;
}

##</code><code>##


<?xml version="1.0" encoding="UTF-8"?>
<response>
	<result>
		<checked_in></checked_in>
		<change_request></change_request>
		<po_number></po_number>
		<correlation_id></correlation_id>
		<cfg_auto_provider></cfg_auto_provider>
		<supported_by></supported_by>
		<u_service_catalog></u_service_catalog>
		<first_discovered></first_discovered>
		<u_oem_part_numbe></u_oem_part_numbe>
		<sent_for_repair></sent_for_repair>
		<owned_by></owned_by>
		<gl_account></gl_account>
		<managed_by></managed_by>
		<asset></asset>
		<u_project_id></u_project_id>
		<maintenance_schedule></maintenance_schedule>
		<u_chg></u_chg>
		<category></category>
		<delivery_date></delivery_date>
		<install_status></install_status>
		<u_maintenance_window></u_maintenance_window>
		<virtual></virtual>
		<u_sub_class></u_sub_class>
		<dns_domain></dns_domain>
		<u_incident></u_incident>
		<u_parts_software_needed></u_parts_software_needed>
		<change_control></change_control>
		<checked_out></checked_out>
		<u_decommission_stamp></u_decommission_stamp>
		<purchase_date></purchase_date>
		<order_date></order_date>
		<u_template></u_template>
		<skip_sync></skip_sync>
		<lease_id></lease_id>
		<u_sevice_options></u_sevice_options>
		<vendor></vendor>
		<sys_id></sys_id>
		<u_maint_contract_sla></u_maint_contract_sla>
		<sys_created_by></sys_created_by>
		<u_sla_support_tie></u_sla_support_tie>
		<subcategory></subcategory>
		<start_date></start_date>
		<comments></comments>
		<location>
			<link></link>
			<value></value>
		</location>
		<unverified></unverified>
		<justification></justification>
		<u_disposal_date></u_disposal_date>
		<sys_tags></sys_tags>
		<sys_domain>
			<link></link>
			<value></value>
		</sys_domain>
		<sys_mod_count></sys_mod_count>
		<cost_cc></cost_cc>
		<u_total_purchase_cost></u_total_purchase_cost>
		<monitor></monitor>
		<sys_updated_on></sys_updated_on>
		<warranty_expiration></warranty_expiration>
		<invoice_number></invoice_number>
		<fqdn></fqdn>
		<cost></cost>
		<u_retail_grp></u_retail_grp>
		<u_server_type></u_server_type>
		<ip_address></ip_address>
		<u_manufacture_date_dummy></u_manufacture_date_dummy>
		<last_discovered></last_discovered>
		<model_id>
			<link></link>
			<value></value>
		</model_id>
		<manufacturer></manufacturer>
		<u_inc>false</u_inc>
		<company></company>
		<due></due>
		<cfg_auto_management_server></cfg_auto_management_server>
		<u_proposed></u_proposed>
		<u_change></u_change>
		<u_work_notes></u_work_notes>
		<u_store_location></u_store_location>
		<asset_tag></asset_tag>
		<discovery_source></discovery_source>
		<u_application_id></u_application_id>
		<assignment_group></assignment_group>
		<can_print></can_print>
		<u_problem></u_problem>
		<department></department>
		<u_manufacture_date></u_manufacture_date>
		<support_group>
			<link></link>
			<value></value>
		</support_group>
		<u_exclusion></u_exclusion>
		<sys_created_on></sys_created_on>
		<u_display_name></u_display_name>
		<u_alias></u_alias>
		<cost_center></cost_center>
		<short_description></short_description>
		<sys_updated_by></sys_updated_by>
		<name></name>
		<u_environment></u_environment>
		<u_function></u_function>
		<due_in></due_in>
		<u_change_approver></u_change_approver>
		<install_date></install_date>
		<assigned></assigned>
		<u_active_stamp></u_active_stamp>
		<u_retail_group></u_retail_group>
		<serial_number></serial_number>
		<u_work_notes__asset_></u_work_notes__asset_>
		<repair_contract_id></repair_contract_id>
		<assigned_to></assigned_to>
		<mac_address></mac_address>
		<model_number></model_number>
		<schedule></schedule>
		<u_ci_id></u_ci_id>
		<returned_from_repair></returned_from_repair>
		<ng_assignment_flag></ng_assignment_flag>
		<u_procurement_product_number></u_procurement_product_number>
		<sys_class_name></sys_class_name>
		<attributes></attributes>
		<u_location_stamp></u_location_stamp>
		<fault_count></fault_count>
		<cfg_auto_change></cfg_auto_change>
	</result>
</response>';