VPC Endpoint for Amazon S3: Simple Connectivity From AWS

Let’s discuss VPC Endpoint’s value, common use cases, and how to get it up and running with the AWS CLI.

Last month Amazon Web Services introduced VPC Endpoint for Amazon S3. In this article, I am going to explain exactly what this means, how it will change – and improve – the way AWS resources communicate with each other, and how you can get it running with the AWS CLI.

Not that it’s quite complete yet, mind you:

Currently, we support endpoints for connections with Amazon S3 within the same region only. We’ll add support for other AWS services later.

Accessing S3 the old way (without VPC Endpoint)

Traditionally, when creating a VPC with a private subnet you would set up security groups and access control lists (ACLs) to control inbound and outbound traffic. Because this is a private subnet, by default it has no access to any outside public resources. Consequently, should you need access to an outside resource, you would need to set up an Internet Gateway and route traffic through a NAT instance.

So, for example, if your EC2 instance runs an application that needs access to a file stored in an S3 bucket, before VPC Endpoint, this illustrates the only way it could be done:

VPC Endpoint: A private subnet with the main route table set up
A private subnet with the main route table set up

Accessing S3 with VPC Endpoint

Now, however, accessing S3 resources from within a private VPC subnet is much simpler. There’s no longer any need to configure a gateway or NAT instances. And as an added bonus, these endpoints are easy to set up, highly reliable, and provide a secure connection to S3.

VPC Endpoint for Amazon S3
With VPC Endpoint for Amazon S3, accessing buckets is a much simpler process

If you’d prefer to work with the console to create a VPC Endpoint, you can easily follow the clear directions from the official AWS Blog. However, I am going to show you how to do it using the AWS CLI.  (By the way, Cloud Academy has a great course guiding you through the AWS CLI if you could use some help).

Creating and Using VPC Endpoints with the AWS CLI

When we create our VPC endpoint we will use the following commands

  1. describe-route-tables (Get our VPC Id and route table for the endpoint)
  2. create-vpc-endpoint (Create your VPC endpoint)
  3. describe-vpc-endpoints (List your VPC endpoint)
  4. delete-vpc-endpoints (Delete a VPC endpoint)

So first, get our VPC ID and route table ID to use for the endpoint

$ aws ec2 describe-route-tables

Your output should look something like this:

--------------------------------------------------------------------------------------------------------
|                                          DescribeRouteTables                                         |
+------------------------------------------------------------------------------------------------------+
||                                             RouteTables                                            ||
|+-------------------------------------------------+--------------------------------------------------+|
||  RouteTableId                                   |  rtb-0404a561                                    ||
||  VpcId                                          |  vpc-731e0711                                    ||
|+-------------------------------------------------+--------------------------------------------------+|
|||                                           Associations                                           |||
||+------------------------------------------------------+-------------------------------------------+||
|||  Main                                                |  False                                    |||
|||  RouteTableAssociationId                             |  rtbassoc-a4339dc1                        |||
|||  RouteTableId                                        |  rtb-0404a561                             |||
|||  SubnetId                                            |  subnet-fcbb5b99                          |||
||+------------------------------------------------------+-------------------------------------------+||
|||                                              Routes                                              |||
||+-----------------------------------------------------+--------------------------------------------+||
|||  DestinationCidrBlock                               |  172.31.0.0/16                             |||
|||  GatewayId                                          |  local                                     |||
|||  Origin                                             |  CreateRouteTable                          |||
|||  State                                              |  active                                    |||
||+-----------------------------------------------------+--------------------------------------------+||
|||                                               Tags                                               |||
||+---------------------------------+----------------------------------------------------------------+||
|||  Key                            |  Name                                                          |||
|||  Value                          |  endpointroute                                                 |||
||+---------------------------------+----------------------------------------------------------------+||
||                                             RouteTables                                            ||
|+-------------------------------------------------+--------------------------------------------------+|
||  RouteTableId                                   |  rtb-b1849cd3                                    ||
||  VpcId                                          |  vpc-731e0711                                    ||
|+-------------------------------------------------+--------------------------------------------------+|
|||                                           Associations                                           |||
||+------------------------------------------------------+-------------------------------------------+||
|||  Main                                                |  True                                     |||
|||  RouteTableAssociationId                             |  rtbassoc-9f0f14fd                        |||
|||  RouteTableId                                        |  rtb-b1849cd3                             |||
||+------------------------------------------------------+-------------------------------------------+||
|||                                              Routes                                              |||
||+----------------------+---------------------------+----------------+-------------------+----------+||
||| DestinationCidrBlock |  DestinationPrefixListId  |   GatewayId    |      Origin       |  State   |||
||+----------------------+---------------------------+----------------+-------------------+----------+||
|||  172.31.0.0/16       |                           |  local         |  CreateRouteTable |  active  |||
|||  0.0.0.0/0           |                           |  igw-1b312779  |  CreateRoute      |  active  |||
|||                      |  pl-6ca54005              |  vpce-d7b652be |  CreateRoute      |  active  |||
||+----------------------+---------------------------+----------------+-------------------+----------+||

This tells me that my VPC ID is vpc-731e0711, and my Route Table Id  (the one connected to a subnet) is rtb-0404a561.
Now let’s create a VPC endpoint. Remember that AWS currently supports endpoints within a single region, so we should note that my default region is  ap-southeast-2.

$ aws ec2 create-vpc-endpoint --vpc-id vpc-731e0711 --service-name com.amazonaws.ap-southeast-2.s3 --route-table-ids rtb-0404a561

Here’s my output:

-------------------------------------------------------------------------------------------------------------------------------------------
|                                                            CreateVpcEndpoint                                                            |
+-----------------------------------------------------------------------------------------------------------------------------------------+
||                                                              VpcEndpoint                                                              ||
|+-------------------+-------------------------------------------------------------------------------------------------------------------+|
||  CreationTimestamp|  2015-06-04T02:45:52Z                                                                                             ||
||  PolicyDocument   |  {"Version":"2008-10-17","Statement":[{"Sid":"","Effect":"Allow","Principal":"*","Action":"*","Resource":"*"}]}   ||
||  ServiceName      |  com.amazonaws.ap-southeast-2.s3                                                                                  ||
||  State            |  available                                                                                                        ||
||  VpcEndpointId    |  vpce-97b652fe                                                                                                    ||
||  VpcId            |  vpc-731e0711                                                                                                     ||
|+-------------------+-------------------------------------------------------------------------------------------------------------------+|
|||                                                            RouteTableIds                                                            |||
||+-------------------------------------------------------------------------------------------------------------------------------------+||
|||  rtb-0404a561                                                                                                                       |||
||+-------------------------------------------------------------------------------------------------------------------------------------+||

You should now have a VpcEndpoint connecting your VPC to an Amazon S3 service in the region you chose. You can now list your VpcEndpoint and the output should be similar to what you got above – unless you created more than one VpcEndpoint:

$ aws ec2 describe-vpc-endpoints

Finally, if you don’t plan on using this again, you can delete the VpcEndpoint using the following:

$ aws ec2 delete-vpc-endpoints --vpc-endpoint-ids vpce-97b652fe

What does all this now mean?

Even once you create a VPC Endpoint, the S3 public endpoints and DNS names will continue to work as they always have. All that the EndPoint does is add a new way by which the requests are routed from your private subnet to S3. Remember also that endpoints are virtual devices: they are horizontally scaled, redundant, and highly available VPC components that allow low-risk communication between instances in your VPC and AWS services.

What an endpoint effectively does is enable instances in your VPC to use their private IP addresses to communicate with resources in other services. Consequently, your instances do not require public IP addresses, and you do not need an Internet Gateway, a NAT instance, or a virtual private gateway in your VPC. This is because you use endpoint policies to control access to resources in other services. Traffic between your VPC and the AWS service does not leave the Amazon network.

Best of all, there is no additional charge for using endpoints. You will, of course, be charged standard charges for data transfer and resource use.

Avatar

Written by

Michael Sheehy

I have been UNIX/Linux System Administrator for the past 15 years and am slowly moving those skills into the AWS Cloud arena. I am passionate about AWS and Cloud Technologies and the exciting future that it promises to bring.


Related Posts

Amanda Cross
Amanda Cross
— April 9, 2021

New Content: Platforms, Programming, and DevOps – Something for Everyone

This month our team of expert certification specialists released three new or updated learning paths, 16 courses, 13 hands-on labs, and four lab challenges! New content on Cloud Academy You can always visit our Content Roadmap to see what’s just released as well as what’s coming soon....

Read more
  • alibaba
  • AWS
  • Azure
  • DevOps
  • Google Cloud Platform
  • programming
  • Security
Luca Casartelli
Luca Casartelli
— March 31, 2021

Mastering AWS Organizations Service Control Policies

Service Control Policies (SCPs) are IAM-like policies to manage permissions in AWS Organizations. SCPs restrict the actions allowed for accounts within the organization making each one of them compliant with your guidelines. SCPs are not meant to grant permissions; you should consider ...

Read more
  • AWS
  • Organizations
  • SCP
Amanda Cross
Amanda Cross
— March 12, 2021

New Content: Focus on DevOps and Programming Content this Month

This month our team of expert certification specialists released 12 new or updated learning paths, 15 courses, 25 hands-on labs, and four lab challenges! New content on Cloud Academy You can always visit our Content Roadmap to see what’s just released as well as what’s coming soon. Ja...

Read more
  • alibaba
  • AWS
  • Azure
  • DevOps
  • Google Cloud Platform
  • programming
Amanda Cross
Amanda Cross
— February 12, 2021

New Content: Get Ready for the CISM Cert Exam & Learn About Alibaba, Plus All the AWS, GCP, and Azure Courses You Know You Can Count On

This month our team of intrepid certification specialists released five learning paths, seven courses, 19 hands-on labs, and three lab challenges!  One particularly interesting new learning path is Certified Information Security Manager (CISM) Foundations. After completing this learn...

Read more
  • alibaba
  • AWS
  • Azure
  • cism
  • DevOps
  • Google Cloud Platform
  • programming
Avatar
Cloud Academy Team
— January 31, 2021

Which Certifications Should I Get?

The old AWS slogan, “Cloud is the new normal” is indeed a reality today. Really, cloud has been the new normal for a while now and getting credentials has become an increasingly effective way to quickly showcase your abilities to recruiters and companies. With all that in mind, the s...

Read more
  • AWS
  • Azure
  • Certifications
  • Cloud Computing
  • Google Cloud Platform
Avatar
Andrew Larkin
— January 31, 2021

The 12 AWS Certifications: Which is Right for You and Your Team?

As companies increasingly shift workloads to the public cloud, cloud computing has moved from a nice-to-have to a core competency in the enterprise. This shift requires a new set of skills to design, deploy, and manage applications in cloud computing. As the market leader and most ma...

Read more
  • AWS
  • AWS Certifications
Avatar
Stuart Scott
— January 29, 2021

AWS Certified Solutions Architect Associate: A Study Guide

Want to take a really impactful step in your technical career? Explore the AWS Solutions Architect Associate certificate. Its new version (SAA-C02) was released on March 23, 2020. The AWS Solutions Architect - Associate Certification (or Sol Arch Associate for short) offers some ...

Read more
  • AWS
  • AWS Certifications
  • AWS Certified Solutions Architect Associate
Amanda Cross
Amanda Cross
— January 7, 2021

New Content: AWS Terraform, Java Programming Lab Challenges, Azure DP-900 & DP-300 Certification Exam Prep, Plus Plenty More Amazon, Google, Microsoft, and Big Data Courses

This month our Content Team continues building the catalog of courses for everyone learning about AWS, GCP, and Microsoft Azure. In addition, this month’s updates include several Java programming lab challenges and a couple of courses on big data. In total, we released five new learning...

Read more
  • AWS
  • Azure
  • DevOps
  • Google Cloud Platform
  • Machine Learning
  • programming
Avatar
Stuart Scott
— December 17, 2020

Where Should You Be Focusing Your AWS Security Efforts?

Another day, another re:Invent session! This time I listened to Stephen Schmidt’s session, “AWS Security: Where we've been, where we're going.” Amongst covering the highlights of AWS security during 2020, a number of newly added AWS features/services were discussed, including: AWS Audit...

Read more
  • AWS
  • AWS re:Invent
  • cloud security
Joe Nemer
Joe Nemer
— December 4, 2020

AWS re:Invent: 2020 Keynote Top Highlights and More

We’ve gotten through the first five days of the special all-virtual 2020 edition of AWS re:Invent. It’s always a really exciting time for practitioners in the field to see what features and services AWS has cooked up for the year ahead.  This year’s conference is a marathon and not a...

Read more
  • AWS
  • AWS Glue Elastic Views
  • AWS re:Invent
Bryony Harrower
Bryony Harrower
— November 6, 2020

WARNING: Great Cloud Content Ahead

At Cloud Academy, content is at the heart of what we do. We work with the world’s leading cloud and operations teams to develop video courses and learning paths that accelerate teams and drive digital transformation. First and foremost, we listen to our customers’ needs and we stay ahea...

Read more
  • AWS
  • Azure
  • content roadmap
  • GCP
Joe Nemer
Joe Nemer
— October 25, 2020

Excelling in AWS, Azure, and Beyond – How Danut Prisacaru Prepares for the Future

Meet Danut Prisacaru. Danut has been a Software Architect for the past 10 years and has been involved in Software Engineering for 30 years. He’s passionate about software and learning, and jokes that coding is basically the only thing he can do well (!). We think his enthusiasm shines t...

Read more
  • AWS
  • careers
  • champions
  • upskilling