Query EC2 tags from within instance

Question

Amazon recently added the wonderful feature of tagging EC2 instances with key-value pairs to make management of large numbers of VMs a bit easier.

Is there some way

Answer 1

I have pieced together the following that is hopefully simpler and cleaner than some of the existing answers and uses only the AWS CLI and no additional tools.

This code example shows how to get the value of tag 'myTag' for the current EC2 instance:

Using describe-tags:

export AWS_DEFAULT_REGION=us-east-1
instance_id=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
aws ec2 describe-tags \
  --filters "Name=resource-id,Values=$instance_id" 'Name=key,Values=myTag' \
  --query 'Tags[].Value' --output text

Or, alternatively, using describe-instances:

aws ec2 describe-instances --instance-id $instance_id \
  --query 'Reservations[].Instances[].Tags[?Key==`myTag`].Value' --output text