I have VPC with two private subnets in two different AZ and
I am trying to create a VPC Endpoint for connecting lambda to my database in private one of subnet
But I need SNS also for sending message to users based on my lambda function
Do I need to create another endpoint for SNS in that subnet or I can attach multiple services to the same endpoint
I know NAT gateway is an option but it is costly than endpoints
Please suggest best way to do this
Thanks,
Monika
No. A VPC Endpoint is always for a specific service.
By the way, you do not require a VPC Endpoint for Lambda in your situation. Simply configure the AWS Lambda function to connect to the private subnets in the VPC. This is an in-built capability of Lambda functions and the do not require a VPC Endpoint to access the subnets.
Related
I am connecting to AWS DocumentDB from a Lambda function. In order to be able to do this I had to attach lambda to the default VPC (that's where DocumentDB cluster is running) and the default (public) subnets. But, this has caused my Lambda to timeout whenever trying make an outbound request, e.g. push message to SQS. This, I want to avoid.
So what is the recommended way of connecting to DocumentDB without loosing functionality that occurs when putting Lambda in the VPC? There's gotta be a simple solution.
Lambda functions in a VPC never get a public IP address. So if the function needs to access both VPC resources and other resources outside of the VPC the function has to be deployed only to private subnets with routes to a NAT Gateway.
Alternatively, if the only external resources you need to access are other AWS services, then you could add VPC Endpoints for those services to the VPC.
I am working on a AWS lambda in which i want to use DynamoDB and a VPC(Amazon elasticcache for redis). But I was getting time out error when trigger lambda
You either need to create a DyanmoDB VPC Endpoint in the VPC, or add a NAT Gateway to the VPC, and only deploy the Lambda function in subnets that have a route to the NAT Gateway.
Depending on the VPC configuration subnet/Security Group of your lambda,
If your lambda is in a private subnet :
If you want a secure internal way, you can pass with VPC endpoint
Else if you want to pass with internet, you must have a NAT Gateway.
Check also the security groups/NACLS....
I am working on a project where my main lambda function is in a VPC in private subnet and some sister lambda functions in a different VPC which are in their own private subnets. How can I go about calling these sister lambdas's from the main lambda across VPC without giving internet access to each of them via a NAT gateway linking to a public subnet which has an internet gateway attached to it.
Other AWS services that my main lambda invokes are:
1. S3
2. Dynamodb
3. Autoscaling
4. ECS
5. RDS
This can be done, but there are some complex steps involved.
First of all, when you use aws-sdk, the calls are made through the internet. To avoid this situation and access the services within the AWS network, The AWS has introduced some private VPC endpoints. I have only used S3 and API gateway private endpoints to date. But there is more type of VPC endpoints.
This is how I would do today,
setup a private API gateway API to invoke lambda - The private API's are only accessible through a private VPC endpoint for API gateway.
create a private VPC endpoint for API gateway.
setup VPC peering between the VPCs
(from the sister lambda on other VPC) invoke the API through the VPC endpoints public DNS URL
The drawback of adding an API in front of the lambda is, the API has a hard timeout of 29 seconds.
hope this helps.
I'd like to have a lambda expression that every hour makes a query on RDS database, pull some ARN (device tokens) and then sends these devices a notification via SNS. My desire is to remain inside the VPC and I'd like to avoid using NAT due to its cost. Should i create a VPC endpoint (is this called AWS PrivateLink?) that can reach out SNS+RDS? Is NAT and Endpoint similar in billing? Globally is this the right way to achieve a "cron sending notifications" on AWS?
RDS is reachable inside the VPC without the endpoint isn't it?
This is totally possibly
Your lambda can run in a private subnet in the VPC that communicates with your RDS database over the network on port 3306. Make sure your security group and NACL rules allow this.
You then need to create a VPC endpoint to your SNS service. Be sure your route table includes this route.
The main difference between VPC endpoints and AWS Privatelink is the following:
A VPC endpoint enables you to privately connect your VPC to supported AWS services. SNS, Kinesis, SQS, S3,....
While AWS Privatelink is more about creating your own application in your VPC and configuring it as an AWS PrivateLink-powered service (referred to as an endpoint service). Other AWS principals can create a connection from their VPC to your endpoint service using an interface VPC endpoint.
VPC endpoints are free. Nat Gateways cost per hour per GB.
I need to connect dynamoDb and elasticache from aws-lambda (otherthan using NAT Gateway).
ElastiCache provides essential caching methods along with help in making the Lambda state-ful. The concern is that for Lambda to work nice with DynamoDB it should be set to NoVPC.
If we have to use ElastiCache, Lambda and both have to be in the same VPC.TO use Both ElastiCache and DynamoDB together is quite a challenge specially with Lambda. Given the VPC challenges.Do you have any suggestions to make this easier?
A Lambda function would have to have VPC access to connect to ElastiCache, and it would have to have access to resources outside the VPC to access DynamoDB so it would require a NAT gateway. There is no way to provide access to both of those services to a single Lambda function without enabling VPC access and setting up a NAT gateway.
If you just need a Redis server and aren't required specifically to use ElasiCache, then you could use a RedisLabs instance which wouldn't require you to enable VPC access on your Lambda function.
There is now a relatively easy solution for DynamoDb access from a VPC: VPC Endpoints.
"Previously, if you wanted your EC2 (elroy: or lambda) instances in your VPC to be able to access DynamoDB, you had two options. You could use an Internet Gateway (with a NAT Gateway or assigning your instances public IPs) or you could route all of your traffic to your local infrastructure via VPN or AWS Direct Connect and then back to DynamoDB."
"A VPC endpoint for DynamoDB enables Amazon EC2 instances in your VPC to use their private IP addresses to access DynamoDB with no exposure to the public Internet...Your EC2 instances do not require public IP addresses, and you do not need an Internet gateway, a NAT device, or a virtual private gateway in your VPC. You use endpoint policies to control access to DynamoDB. Traffic between your VPC and the AWS service does not leave the Amazon network. "
The above quotes come from the links below. Note the the references to "EC2 instances" apply to lambda contexts as well.
See https://aws.amazon.com/blogs/aws/new-vpc-endpoints-for-dynamodb/
and
http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/vpc-endpoints-dynamodb.html