Cisco ASA Dynamic NAT Configuration

Here are my configs on all 3 devices ;

ASA Version 8.4(2)
!
hostname ciscoasa
enable password 5QFRjbooNyC4gmxi encrypted
passwd 2KFQnbNIdI.2KYOU encrypted
names
!
interface GigabitEthernet0
 nameif INSIDE
 security-level 100
 ip address 192.168.1.254 255.255.255.0
!
interface GigabitEthernet1
 nameif OUTSIDE
 security-level 0
 ip address 192.168.2.254 255.255.255.0
!
interface GigabitEthernet2
 nameif DMZ
 security-level 50
 ip address 192.168.3.254 255.255.255.0
!
interface GigabitEthernet3
 shutdown
 no nameif
 no security-level
 no ip address
!
interface GigabitEthernet4
 shutdown
 no nameif
 no security-level
 no ip address
!
ftp mode passive
object network PUCLIC_POOL
 range 192.168.2.100 192.168.2.200
object network INTERNAL
 subnet 192.168.1.0 255.255.255.0
object network DMZ_POOL
 range 192.168.3.100 192.168.3.200
object network INSIDE_TO_DMZ
 subnet 192.168.1.0 255.255.255.0
object network INSIDE_TO_OUTSIDE
 subnet 192.168.1.0 255.255.255.0
object network DMZ_TO_OUTSIDE
 subnet 192.168.3.0 255.255.255.0
object network INSIDE
 subnet 192.168.1.0 255.255.255.0
pager lines 24
mtu INSIDE 1500
mtu OUTSIDE 1500
mtu DMZ 1500
icmp unreachable rate-limit 1 burst-size 1
no asdm history enable
arp timeout 14400
!
object network INSIDE_TO_OUTSIDE
 nat (INSIDE,OUTSIDE) dynamic interface
object network INSIDE
 nat (INSIDE,OUTSIDE) dynamic 192.168.2.253
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
timeout tcp-proxy-reassembly 0:01:00
timeout floating-conn 0:00:00
dynamic-access-policy-record DfltAccessPolicy
user-identity default-domain LOCAL
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart warmstart
telnet timeout 5
ssh timeout 5
console timeout 0
threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
username sam password p26VXMQgXge5voSE encrypted privilege 15
!
class-map global_policy
class-map icmp-class
 match default-inspection-traffic
class-map icmp
 match any
class-map inspection_default
!
!
policy-map icmp_policy
 class icmp
  inspect icmp
!
service-policy icmp_policy global
prompt hostname context
call-home reporting anonymous prompt 2
call-home
 profile CiscoTAC-1
  no active
  destination address http https://tools.cisco.com/its/service/oddce/services/DDCEService
  destination address email callhome@cisco.com
  destination transport-method http
  subscribe-to-alert-group diagnostic
  subscribe-to-alert-group environment
  subscribe-to-alert-group inventory periodic monthly
  subscribe-to-alert-group configuration periodic monthly
  subscribe-to-alert-group telemetry periodic daily
crashinfo save disable
Cryptochecksum:d7cfb8f8d5a787d20d1ea7ef88b246d6
: end





hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
!
ip cef
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
username sam password 0 sam
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Ethernet0/0
 ip address 192.168.1.1 255.255.255.0
 half-duplex
!
interface Ethernet0/1
 no ip address
 shutdown
 half-duplex
!
interface Ethernet0/2
 no ip address
 shutdown
 half-duplex
!
interface Ethernet0/3
 no ip address
 shutdown
 half-duplex
!
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
line con 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line aux 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line vty 0 4
 exec-timeout 0 0
 password sam
 logging synchronous
 login 
!
!
end






hostname R2
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
!
ip cef
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
username sam password 0 sam
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Ethernet0/0
 ip address 192.168.2.2 255.255.255.0
 half-duplex
!
interface Ethernet0/1
 no ip address
 shutdown
 half-duplex
!
interface Ethernet0/2
 no ip address
 shutdown
 half-duplex
!
interface Ethernet0/3
 no ip address
 shutdown
 half-duplex
!
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
line con 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line aux 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line vty 0 4
 exec-timeout 0 0
 privilege level 15
 password sam
 logging synchronous
 login 
!
!
end





hostname DMZ
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
!
ip cef
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
username sam password 0 sam
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Ethernet0/0
 ip address 192.168.3.3 255.255.255.0
 half-duplex
!
interface Ethernet0/1
 no ip address
 shutdown
 half-duplex
!
interface Ethernet0/2
 no ip address
 shutdown
 half-duplex
!
interface Ethernet0/3
 no ip address
 shutdown
 half-duplex
!
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
!
!
!
control-plane
!
!
!
!
!
!
!
!
!
!
line con 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line aux 0
 exec-timeout 0 0
 privilege level 15
 logging synchronous
line vty 0 4
 exec-timeout 0 0
 privilege level 15
 password sam
 logging synchronous
 login 
!
!
end