[SOLVED] I have a list of EC2's, and want to loop through the list in bash, does anyone have a way?

Issue

I'm using this command "aws ec2 describe-instances --region us-west-2 --filters "Name=instance-state-name,Values=running" --output table --query 'Reservations[].Instances[].InstanceId'". Returns a list of all my running ec2's in us west 2, i'd like to take each output in this list and loop through each one with another command to see which ones are using ssm. Thanks for all responses.

I've tried making an empty array, but that got me no where.

What I've tried, making variable x an empty list x=[] and then running the above command to try to have outputs added to empty list x=aws ec2 describe-instances --region us-west-2 --filters "Name=instance-state-name,Values=running" --output table --query 'Reservations[*].Instances[*].InstanceId'. In general I am more familiar with python, but this was just meant to be a quick bash tool. error: getNonSSMEC2.sh: line 3: ec2: command not found

Solution

So firstly - when you want to capture bash command output as a variable you need to declare it like this: x=$(ls) or x=`ls`

Regarding loop:

x=`aws ec2 describe-instances --region us-west-2 --filters "Name=instance-state-name,Values=running" --query 'Reservations[*].Instances[*].InstanceId'`
for id in $(echo $x | jq -r ".[0][0]")
do 
  echo $id
done

I assume in the loop you should use this function to get SSM informations: https://docs.aws.amazon.com/cli/latest/reference/ssm/describe-instance-information.html

Btw, you can always use describe-instance-information to get list of ec2 instances instead of using ec2 describe-instances.

Answered By - ZabielskiGabriel

Answer Checked By - Gilberto Lyons (WPSolving Admin)