We have an elasticsearch service deployment at elastic.co. During the creation of the deployment "AWS" was chosen as the cloud platform. We are given an endpoint URL that resolves to a public IP address.
Also, we have an AWS account that has multiple ec2 instances running. When we access elasticsearch service from ec2 instances, the traffic goes through the internet.
Is it possible to make elasticsearch service visible to ec2 instances, as if both are in the same network?
If you want to use a secure connection, you have to use a special subscription called Elasticsearch Service Private. It is mentioned in the FAQs [1]:
We support secure peering using AWS Private Link. To run Elasticsearch Service in a dedicated VPC with a secure connection from your environment, use the Elasticsearch Service Private subscription. For more information, see Set up Elasticsearch Service Private.
There is a guide which outlines all the steps you need to take. [2]
I do not know the pricing details though. In the guide, they state that you need to contact their team in order to get more information. After you get in touch with them and order the Elasticsearch Service Private subscription, they set up a VPC inside their account for you. Next, they create a VPC PrivateLink Endpoint Service and whitelist your account. Finally, they give you the Elasticsearch Service Private Endpoint Service name which you can use to create an Interface VPC Endpoint (powered by PrivateLink). [3]
You should create an interface endpoint in each of the subnets used by your EC2 instances.
After creating the interface endpoints, you are able to access the Elasticsearch endpoint via a DNS name which is added to the AWS DNS servers automatically by PrivateLink. You just have to make sure that your EC2 instances are using the VPC's DNS servers. It should be the default configuration if you did not change the VPC's default DHCP option set.
References
[1] https://www.elastic.co/guide/en/cloud/current/ec-faq.html (see question: "Do you support VPC peering to Elasticsearch Service?")
[2] https://www.elastic.co/guide/en/cloud/current/ec-getting-started-private.html
[3] https://docs.aws.amazon.com/vpc/latest/userguide/vpce-interface.html
Related
What is the difference between Private Link and VPC endpoint? As per the documentation it seems like VPC endpoint is a gateway to access AWS services without exposing the data to internet. But the definition about AWS private link also looks similar.
Reference Link:
https://docs.aws.amazon.com/vpc/latest/userguide/endpoint-services-overview.html
Does Private Link is the superset of VPC endpoint?
It would be really helpful if anyone provides the difference between these two with examples!
Thanks in Advance!
AWS defines them as:
VPC endpoint — The entry point in your VPC that enables you to connect privately to a service.
AWS PrivateLink — A technology that provides private connectivity between VPCs and services.
So PrivateLink is technology allowing you to privately (without Internet) access services in VPCs. These services can be your own, or provided by AWS.
Let's say that you've developed some application and you are hosting it in your VPC. You would like to enable access to this application to services in other VPCs and other AWS users/accounts. But you don't want to setup any VPC peering nor use Internet for that. This is where PrivateLink can be used. Using PrivateLink you can create your own VPC endpoint services which will enable other services to use your application.
In the above scenario, VPC interface endpoint is a resource that users of your application would have to create in their VPCs to connect to your application. This is same as when you create VPC interface endpoint to access AWS provided services privately (no Internet), such as Lambda, KMS or SMS.
There are also Gateway VPC endpoints which is older technology, replaced by PrivateLink. Gateways can only be used to access S3 and DynamoDB, nothing else.
To sum up, PrivateLink is general technology which can be used by you or AWS to allow private access to internal services. VPC interface endpoint is a resource that the users of such VPC services create in their own VPCs to interact with them.
Suppose there is a website xyz.com that I am hosting in a bunch of Ec2 instances, exposed to the outside world thru a Network load balancer.
Now, a client who has his/her own AWS account, wants to access this xyz.com from an Ec2 running in their aws account.
One approach is to go thru the Internet.
However the client wants to avoid the internet route.
He/she wants to use the AWS backbone to reach xyz.com.
The technology that enables that, is AWS Private link.
(note that if you search for Private Link in the AWS services, there will be none.
You will get "End point services" as the closest hit)
So, this is how to route traffic through the AWS backbone:
I, the owner of xyz.com, will create a VPC End Point Service (NOTE the keyword Service here)
The VPC End point service will point to my Network load balancer.
I will then give my VPC End point service name to the client.
The client will create a VPC End Point (NOTE.. this is different from #1).
While creating it, the client will specify the VPC End Point Service name (from #1) that he got from me.
I can choose to be prompted to accept the connection from the client to my VPC End point service.
As soon as I accept it, then the client can reach xyz.com from his/her EC2 instance.
There is no Internet, no direct connect or VPN.. this simply works; and its secure.
And which technology enabled it.. AWS Private link !!!
PRIVATE LINK IS THE ONLY TECHNOLOGY THAT ALLOWS 2 VPCS TO CONNECT THAT HAVE OVERLAPPING CIDR RANGES.
A useful way in understanding differences is in how they technically connect private resources to public services.
Gateway Endpoints route traffic by adding prefix lists within a VPC route table which targets the Gateway endpoint. It is a logical gateway object similar to a Internet Gateway.
In contrast, an Interface Endpoint uses Privatelink to inject into a VPC at the subnet level, via an Elastic Network Interface (ENI), giving network interface functionality, and therefore, DNS and private IP addressing as a means to connect to AWS public services, rather than simply being routed to it.
The differences in connections offer differing advantages and disadvantages (availability, resiliency, access, scalability, and etc), which then dictates how best to connect private resources to public services.
Privatelink is simply a very much abstracted technology to allow a more simplified connection by using DNS. The following AWS re:Invent offers a great overview of Privatelink: https://www.youtube.com/watch?v=abOFqytVqBU
As you correctly mentioned in the question that both VPC endpoint and AWS private link do not expose to internet. On AWS console under VPC, there is a clear option available to create an endpoint. But there is no option/label to create AWS private link. Actually, there is one more option/label called endpoint service. Creating endpoint service is one way to establish AWS private link. At one side of this AWS private link is your endpoint service and at the other side is your endpoint itself. And interestingly we create both these sides in two different VPCs. In other words, you are connecting two VPCs with this private link (instead of using internet or VPC peering).
understand like,
VPC1 got endpoint service ----> private link -----> VPC2 got endpoint
Here endpoint service side is service provider while endpoint is service consumer. So when you have some service (may be some application or s/w) that you think other VPC endpoints can consume you create endpoint service at your end and consumers will create endpoints at there end. When consumers create endpoints at their end they have to give/select your service name and thus private link will be established with your service.
Ultimately you can have multiple consumers of your service just like one to many relationship.
I have create elastic service in AWS with Dev Testing(t2 small)
Detials shown below
VPCvpc-7620c30b
Security Groups
sg-7e9b1759
IAM RoleAWSServiceRoleForAmazonElasticsearchService
AZs and Subnets
us-east-1e: subnet-2f100a11
How to access my VPC endpoint https://vpc-xxx.us-east-1.es.amazonaws.com access from outside.
Kibana is below : https://vpc-xx.us-east-1.es.amazonaws.com/_plugin/kibana/
I am not running on Ec2 instance
From docs:
To access the default installation of Kibana for a domain that resides within a VPC, users must have access to the VPC. This process varies by network configuration, but likely involves connecting to a VPN or managed network or using a proxy server.
One way of setting up the proxy server has been explained in detail in the recent AWS blog post:
How do I use an NGINX proxy to access Kibana from outside a VPC that's using Amazon Cognito authentication?
The instruction could also be adapted to not using Congnito.
Extra links, with other, probably easier setup with ssh tunnels:
How to connect to AWS Elasticsearch cluster from outside of the VPC
How To: Access Your AWS VPC-based Elasticsearch Cluster Locally
SSH Tunnel Access to AWS ElasticSearch Domain and Kibana | Howto
How can I use an SSH tunnel to access Kibana from outside of a VPC with Amazon Cognito authentication?
VPC endpoints are not accessible directly from outside of the VPC.
If you want to allow this you will need to use a proxy instance in your VPC that can connect to the VPC endpoint, then proxy all requests through the EC2 instance in order to access the endpoint.
More information is available here.
I have an existing VPC interface endpoint for elastic load balancer in a VPC A and a NLB in VPC B with a VPC endpoint service associated.
How I can create the association between the VPC interface endpoint and NLB as in the AWS diagram?
According to I can't connect to an endpoint service from my Amazon Virtual Private Cloud (Amazon VPC) interface endpoint using AWS PrivateLink., it looks a request needs to be created.
.
Request that the endpoint service provider accepts the endpoint connection request to activate the connection.
However, I do not see any option to create a request in the VPC endpoint side.
According to Create A VPC Endpoint Service, the request can be created when creating a VPC interface endpoint, but I have already created one.
Please advise how to, or correct me if I misunderstand something.
Go to your VPC Dashboard > Endpoint Service and check under the Endpoint Connections tab. If your VPC endpoint is in the list and the state is Available, then the association you are looking for is established.
One possible reason why you did not have a Pending acceptance status in your VPC endpoint could be that you did not check the Acceptance required box when creating the VPC endpoint service.
Check out AWS New York Summit 2018 - AWS PrivateLink: Fundamentals (SRV211) at 28:08 and 33:33 for the full demo.
I created an ElasticDomain in private subnet which has a VPC endpoint and a security group which allows access from port 443. We want to access this ElasticDomain from another AWS account's EC2 instance. But we are not able to do that.
We tried creating ElasticDomain with a public endpoint which is accessible from anywhere but is not the right option for us.
We are considering to use apache as a reverse proxy and then set up a VPC private-link on a consumer account. Is that a right approach?
AWS PrivateLink via VPC and Network Load Balancer doesn't support ElasticDomain for now.
Check out the following two links:
1) https://aws.amazon.com/blogs/security/how-to-control-access-to-your-amazon-elasticsearch-service-domain/
2) AWS ElasticSearch write to account "A" from lambda in account "B"
According to the AWS documentation on NAT Gateways, they cannot send traffic over VPC endpoints, unless it is setup in the following manner:
A NAT gateway cannot send traffic over VPC endpoints [...]. If your instances in the private subnet must access resources over a VPC endpoint [...], use the private subnet’s route table to route the traffic directly to these devices.
Following this example in the docs, I created the following configuration for my ECS app:
VPC (vpc-app) with CIDR 172.31.0.0/16.
App subnet (subnet-app) with the following route table:
Destination | Target
----------------|-----------
172.31.0.0/16 | local
0.0.0.0/0 | nat-main
NAT Gateway (nat-main) in vpc-app in subnet default-1 with the following Route Table:
Destination | Target
----------------|--------------
172.31.0.0/16 | local
0.0.0.0/0 | igw-xxxxxxxx
Security Group (sg-app) with port 443 open for subnet-app.
VPC Endpoints (Interface type) with vpc-app, subnet-app and sg-app for the following services:
com.amazonaws.eu-west-1.ecr.api
com.amazonaws.eu-west-1.ecr.dkr
com.amazonaws.eu-west-1.ecs
com.amazonaws.eu-west-1.ecs-agent
com.amazonaws.eu-west-1.ecs-telemetry
com.amazonaws.eu-west-1.s3 (Gateway)
It's also important to mention that I've enabled DNS Resolution and DNS Hostnames for vpc-app, as well as the Enable Private DNS Name option for the ecr-dkr and ecr-api VPC endpoints.
I've also tried working only with Fargate containers since they don't have the added complication of the ECS Agent, and because according to the docs:
Tasks using the Fargate launch type only require the com.amazonaws.region.ecr.dkr Amazon ECR VPC endpoint and the Amazon S3 gateway endpoint to take advantage of this feature.
This also doesn't work and every time my Fargate tasks run I see a spike in Bytes out to source under nat-main's Monitoring.
No matter what I try, the EC2 instances (and Fargate tasks) in the subnet-app are still pulling images using nat-main and not going to the local address of the ECR service.
I've restarted the ECS Agent and made sure to check all the boxes in the ECS Interface VPC Endpoints guide AND the ECR Interface Endpoints guide.
What am I missing here?
Any help would be appreciated.
After many hours of trial and error, and with lots of help from #jogold, the missing piece was found in this blog post:
The next step is to create a gateway VPC endpoint for S3. This is necessary because ECR uses S3 to store Docker image layers. When your instances download Docker images from ECR, they must access ECR to get the image manifest and S3 to download the actual image layers.
After I created the S3 Gateway VPCE, I forgot to add its address to subnet-app's routing table, so although the initial request to my ECR URI was made using the internal address, the downloading of the image from S3 still used the NAT Gateway.
After adding the entry, the network usage of the NAT Gateway dropped dramatically.
More information on how to setup Gateway VPCE can be found here.
Interface VPC endpoints work with DNS resolution, not routing.
In order for you configuration to work, you need to ensure that you checked Enable Private DNS Name when you created the endpoint. This enables you to make requests to the service using its default DNS hostname instead of the endpoint-specific DNS hostnames.
From the documentation:
When you create an interface endpoint, we generate endpoint-specific DNS hostnames that you can use to communicate with the service. For AWS services and AWS Marketplace partner services, you can optionally enable private DNS for the endpoint. This option associates a private hosted zone with your VPC. The hosted zone contains a record set for the default DNS name for the service (for example, ec2.us-east-1.amazonaws.com) that resolves to the private IP addresses of the endpoint network interfaces in your VPC. This enables you to make requests to the service using its default DNS hostname instead of the endpoint-specific DNS hostnames. For example, if your existing applications make requests to an AWS service, they can continue to make requests through the interface endpoint without requiring any configuration changes.
The alternative is to update your application to use your endpoint-specific DNS hostnames.
Note that to use private DNS names, DNS resolution and DNS hostnames must be enabled for your VPC:
Also note that in order to use ECR/ECS without a NAT gateway, you need to configure a S3 endpoint (gateway, requires route table update) to allow instances to download the image layers from the underlying private Amazon S3 buckets that host them. More information in Setting up AWS PrivateLink for Amazon ECS, and Amazon ECR