Show HN: Lambda function to make a hosts file from your running EC2 instances

2 points

8 years ago

I was so annoyed at how hard it is to identify instances in a VPC I wrote this to make a hosts file and put it in an S3 bucket.

If you give your EC2 instance a "hostname" tag then this will be added as an alias for that host.

https://gist.github.com/bootrino/7ae38d38dabf0a4be1093742471...

This article gives an overview for how to configure AWS to run a Lambda function like this, triggered any time there is a state change in your EC2 instances.

https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/L...

Output looks like this:

  ubuntu@ip-10-0-0-229:~$ --> curl https://s3.eu-west-1.amazonaws.com/bucketname/hosts
  10.0.0.196               ip-10-0-0-196.eu-west-1.compute.internal
  10.0.0.229               ip-10-0-0-229.eu-west-1.compute.internal somecustomhostname.foo.com
  10.0.0.138               ip-10-0-0-138.eu-west-1.compute.internal
  10.0.1.53                ip-10-0-1-53.eu-west-1.compute.internal
  10.0.0.4                 ip-10-0-0-4.eu-west-1.compute.internal
  ubuntu@ip-10-0-0-229:~$ -->