AWS + Elastic Beanstalk + MongoDB

Question

I am trying to setup my microservices architecture using AWS Elastic Beanstalk and Docker. That is very easy to do, but when I launch the environment, it launches into the default VPC, thus giving public IP's to the instances. Right now, that's not too much of a concern.

What I am having a problem with is how to set up the MongoDB architecture. I have read: recommended way to install mongodb on elastic beanstalk but still remain unsure on how to set this up.

So far I have tried:

• Using the CloudFormation template from AWS here: http://docs.aws.amazon.com/quickstart/latest/mongodb/step2b.html to launch a primary with 2 replica node setup into the default VPC, but this gives and assigns public access to the Mongo nodes. I also am not sure how to connect my application since this does not add a NAT instance - do I simply connect directly to the primary node? In case of failure for this node, will the secondary node's IP become the same as that of the primary node so that all connections remain consistent? Or do I need to add my own NAT instance?
• I have also tried launching MongoDB into its own VPC (https://docs.aws.amazon.com/quickstart/latest/mongodb/step2a.html) and giving access via the NAT, but this means having two different VPCs (one for my EB instances and one for the MongoDB). In this case would I connect to the NAT from my EB VPC in order to route requests to the databases?
• I have also tried launching a new VPC for the MongoDB architecture first and then trying to launch EB into this VPC. For some reason, the load balancing setup won't let me add into the subnets, giving me the error: "Custom Availability Zones option not supported for VPC environments".

I am trying to launch all this in us-west-1. It's been two days now and I have no idea where to go or what the right way is to tackle this issue. I want the databases to be private (no public access) with a NAT gateway, so ideally my third method seems what I want, but I cannot seem to add the new EB instances/load balancer into the newly-created MongoDB VPC. This is the setup I'm going for: http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/images/default-vpc-diagram.png but I am trying to use the templates to do this.

What am I doing wrong here? Any help would be much, much appreciated. I have read up a lot about this but still am not sure where to go from here.

Thanks a lot in advance!

Answer 1

Im having this same issue. There seems to be a complete lack of documentation on how to connect an Elastic Beanstalk node.js / express app with the aws Quickstart mongodb cluster set up documentation. When I run the aws mongo quickstart though it launches a NAT which is public and also a private primary node... maybe this is part of your issue?