You can use a network address translation (NAT) instance in a public subnet in your VPC to enable instances in the private subnet to initiate outbound IPv4 traffic to the Internet or other AWS services, but prevent the instances from receiving inbound traffic initiated by someone on the Internet. LinkedIn https://www.linkedin.com/today/author/mohan-reddy-79a57014b Youtube https://www.youtube.com/user/VepsunTechnologies Vepsun http://www.vepsun.in/

1. NAT Instance
You can use a network address translation (NAT) instance in a public subnet in your VPC to
enable instances in the private subnet to initiate outbound IPv4 traffic to the Internet or other
AWS services, but prevent the instances from receiving inbound traffic initiated by someone on
the Internet.
NAT Instance Configuration
1) Once Loginto the console,gotoVPC

2. 2) Create VPC(virtual private cloud,it’saisolatednetwork)
(ClickonyourVPC--- give aname---give IPv4CIDR----clickonCreate)
3) Create subnet( Create small networkunderbignetwork(VPC))
(Subnetname—selectVPC--- give IPv4---clickoncreate)
Here I givenname calledpublicsubnet
PublicSubnet:- The subnetwhich associatedtointernetgateway

3. 4) Create one more subnet
(Subnetname—selectVPC--- give IPv4---clickoncreate)
Here I givenname calledprivate subnet
Private Subnet:- The subnetwhichisnotassociatedtointernetgateway
5) Create InternetGateway
(Itallows communication between instances in your VPC and the Internet)
(Go to Internet Gateway---give a name---then select Internet Gateway---Action---Attach
to VPC)

4. 6) AddInternetGatewaytoroute Table,here I am addingInternetgatewaytomainroute table.
(Mainroute table ---routes—edit---add)

5. launchingNatInstance
7) Go to ec2 Console
8) Clickon Instance,launchinstance
Go to AMI, selectCommunityAMI,Select“AMAZON-ami-VPC-NAT-HVM”

6. Under respectiveVPCwithEnabledPublicIP
Launch Instance withdefaultsetting.
9) SelectNatInstance DetachSource and destinationcheck

7. 10) Create Customroute table
(Route Table---CreateRoute table---give aname---selectvpc---clickonCreate)
11) ADD Nat Instance IDto CustomRoute table
AndAssociate Private Subnettothisroute table

8. To testNAT Instance
Create 2 instancesone withpublicIPinPublicSubnetandOne more underprivate subnetwith
private IP
(PublicIPInstance canconnectdirectlybecause itconnectedtoIGW andassignedpublicIP,
Private IPinstance We can’t connectdirectly,take remote frompublicIPInstance)

9. Private IPInstance machine Connectedandmachine gettingInternet,thismachine getting
internetfromNATInstance.
Use Tracert 8.8.8.8 command,it will show fromwhere instance gettingInternet.