Query EC2 tags from within instance

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 to query these tags in the same way as some of the other user-set data? For example:

$ curl http://169.254.169.254/latest/meta-data/placement/availability-zone
us-east-1d

Is there some similar way to query the tags?

The following bash script returns the Name of your current ec2 instance (the value of the "Name" tag). Modify TAG_NAME to your specific case.

TAG_NAME="Name"
INSTANCE_ID="`wget -qO- http://instance-data/latest/meta-data/instance-id`"
REGION="`wget -qO- http://instance-data/latest/meta-data/placement/availability-zone | sed -e 's:\([0-9][0-9]*\)[a-z]*\$:\\1:'`"
TAG_VALUE="`aws ec2 describe-tags --filters "Name=resource-id,Values=$INSTANCE_ID" "Name=key,Values=$TAG_NAME" --region $REGION --output=text | cut -f5`"

To install the aws cli

sudo apt-get install python-pip -y
sudo pip install awscli

In case you use IAM instead of explicit credentials, use these IAM permissions:

{
  "Version": "2012-10-17",
  "Statement": [
    {    
      "Effect": "Allow",
      "Action": [ "ec2:DescribeTags"],
      "Resource": ["*"]
    }
  ]
}

Once you've got ec2-metadata and ec2-describe-tags installed (as mentioned in Ranieri's answer above), here's an example shell command to get the "name" of the current instance, assuming you have a "Name=Foo" tag on it.

Assumes EC2_PRIVATE_KEY and EC2_CERT environment variables are set.

ec2-describe-tags \
  --filter "resource-type=instance" \
  --filter "resource-id=$(ec2-metadata -i | cut -d ' ' -f2)" \
  --filter "key=Name" | cut -f5

This returns Foo.

You can use a combination of the AWS metadata tool (to retrieve your instance ID) and the new Tag API to retrieve the tags for the current instance.

Query EC2 tags from within instance

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