create a Powershell code that works with AWS: to list EC2 Key Pairs that are not in use by instances

Question

I am looking to create a Powershell code that works with AWS: to list EC2 Key Pairs that are not in use by instances.

aws ec2 --profile default describe-key-pairs --query KeyPairs[].[KeyName] --output text |xargs -I {} aws ec2 --profile default describe-instances --filters Name=key-name,Values={} --query Reservations[].Instances[].[KeyName,InstanceId] --output text| uniq

this code dosent work for powershell

Answer 1

You need to work with AWS Powershell Module.

The trick here is work with 2 cmdlet function - Get-EC2instance and Get-EC2KeyPair . First of all, you need to get all the keys that in use right now. Later, you need to get all key pairs and filter them by basic for each and if statement.

Take a look at the following code snippet:

Import-Module AWSPowerShell
$keysInUse = @()
$keysNotInUse = @()

#Set AWS Credential        
Set-AWSCredential -AccessKey "AccessKey" -SecretKey "SecretKey"        

#Get ec2 key name from each instance
$allInstancesKeys = (Get-EC2instance  -Region "YourRegion").Instances.KeyName

#Get all key based on region and check if there's an instance who use this key
Get-EC2KeyPair -Region "YourRegion" | % {

    if($_.KeyName -notin $allInstancesKeys)
    {
        $keysNotInUse += $_.KeyName
    }

    else
    {
        $keysInUse += $_.KeyName
    }

} 

Write-Output "Keys not in use: $($keysNotInUse -join ',')\n
Keys in use: $($keysInUse -join ',')"

The instances i own and key name: