How to find OS of an EC2 instance using AWS CLI

Question

How can you find out the OS running on an EC2 instance using AWS CLI.

The ec2 describe-instance command spits out a lot of information , but there is nothing indicating the OS .

I also tried ec2 describe-images on a specific image. Again, there doesn't seem to be any indication of OS.

Help..?

Answer 1

Here's a quick way to list the Platform field, which at least distinguishes between Windows and Linux:

aws ec2 describe-instances --query 'Reservations[*].Instances[*].[InstanceId,Platform]' --output text
i-78b4ef47  windows
i-b8ae3386  windows
i-9d3611a2  None
i-1c57c651  windows
i-a241ec91  None
i-7d26b630  None

Answer 2

Try this command:

aws ec2 describe-images --image-ids $(aws ec2 describe-instances --instance-ids i-xxxxxxxxxxxxx --query 'Reservations[0].Instances[0].ImageId' --output text) --query 'Images[0].Name'

$() part gets the ImageId using InstanceId.