Setup NAT for the Cisco CCNA w/ Packet Tracer - Part 4

so now that I have networking statically over here we're going to do something that's a lot more useful for configuring that on this side so what we're going to do is we're going to set up NAT on this router to hide the land the local area network ID these private addressed computers 192 168 1 Network we're going to hide it behind this NAT right here and since we have multiple computers here and we have only one public IP address the 210 0.1 address right this is our inside local over here and this is our inside global address right here so we're gonna do is we're going to set up NAT overload on this router so on this router I'm going to hit enter this will be like a port address translation that will enable all of the private computers on the network to adopt the public IP address of the router right so everybody will translate to the one address I'll do a compte to get to the global config mode and to do this what I'm going to do is I'm going to write first of all an access list so access - list 1 it's going to be a standard access list and we're going to permit the 192.168.1.0 Network and we got to put wildcard bits for it let me spread this out so you can see it so 0 dot 0 dot 0 dot 2 5 5 so that's wildcard bits which is the opposite basically of a subnet mask so the subnet mask would be 255 255 255 0 so the wildcard bits is the exact opposite of that so that's going to set up an access list alright permitting the 192 168 1 Network and that's these private addresses over here now I can do my NAT statement so IP NAT inside source and for the source addresses we're going to use list 1 which means access list 1 right access list 1 will be our source addresses right and then for the public IP address that we're going to nap to for our outside address or we're going to use interface whatever the IP addresses on interface serial to slash 0 and we're going to overload it so we're going to do port address translation so all private computers on source on access list 1 will be translated to the IP address on interface serial - slash 0 and we'll need port assignments to do it so hit enter all right and that's done now all I have to do is tell NAT where the inside of our network is and where the outside is so interface serial - slash is 0 right that takes me into interface configuration mode and IP NAT outside that's the outside of our network and then interface FA 0/0 takes us into the interface for Fast Ethernet 0 and that's going to be IP NAT inside alright so that's all done now normally what you'd want to do is you control-c go back to privileged exec mode and do a copy run start which is short for copy running - config space start up - config write and that would save your configuration file so now that we have that set up NAT should be working so these private addresses should translate to this public IP address now the way the test that out is to go into simulation mode right and simulate sending packets across the network so what I'm going to do is I'm going to say Auto capture and then I'm going to go to PC 0 and I'll go to command prompt and I will ping the server on the other side of the net work so that's let's say 200.000 210 0.2 and I'll hit ping right and so now these packets are going across see it there it goes packets going across right there it goes and when it goes across here I'm going to click on it and capture it alright and so there it is I've captured it and you can see here that the inbound PD you details you can see here that the source IP address was 200 1001 destination IP address 200 1002 so sure enough the 192 168 1 dot 100 address right the original source IP address from where the ping was generated right here on this PC has been changed or translated to the public IP address of the router interface right here right and so it worked and we could see it by just examining the packets

Channel: danscourses

Views: 115,564

Keywords: Cisco, CCNA, NAT, overload, configure, packet, tracer

Id: VY3a82ctihk

Length: 5min 29sec (329 seconds)

Published: Thu Apr 28 2011