AWS

When deploying infrastructure with CloudFormation, at some point you will reach a moment when your CloudFormation JSON or YAML file is just too big. It will be too long to get a good overview of what’s in it, manage parameters and all dependencies between resources within the template. Nested stacks may be a solution, but if sometimes you can’t/won' t/don’t use them for whatever reason (for example, it will get to complicated to manage tested stacks or their contents are not reusable between other stacks).

Even if you’re using troposphere to generate your templates, you’ll face the same issue - a very long Python file. Luckily, if you are using troposphere, you’re inherently using Python - which means you can take advantage of it.

Fancy getting in touch with us? Have a question or want to know a bit more about our work? June is the month of conferences in London, and we will be attending them! Here are the details where and when to meet us:

When using AWS ElasticSearch Service, you have multiple ways of controlling access to your cluster. AWS Console gives you some pre-set policies you can use, but the ways of access can be confusing. Using the IP-based access, you can allow access from your EC2 instances. But what if you want to access your cluster from a Lambda?

On more than one occasion I have seen S3 bucket policies set for the predefined users groups: “Everyone” and “Any authenticated AWS user”, but rarely has it been done with understanding of what those groups actually mean. So, if you’ve ever set (or thought of setting) permissions for those, please read on.

Intrusion detection system (IDS) and intrusion prevention system (IPS) tend to be expensive and complicated. In AWS, you can go for much simpler solution - WAF. But that requires you to use Application Load Balancer or CloudFront. But even with WAF, you have to manage a list IP addresses of attackers that should be blocked. Or, if you only ever need to block single IPs for short periods of time, NACLs may be a much easier option! Here’s a walkthrough on how you can implement a terribly simple (yet very powerful) intrusion detection and prevention in AWS with Lambda and DynamoDB Streams for a web application.