Add new tags to AWS EC2 instances found by tag filter

new_tag.ps1

#get instances with specific tag
$tagFilter1 = New-Object Amazon.EC2.Model.Filter
$tagFilter1.Name = "tag:Environment Name"
$tagFilter1.Value.Add("MyEnv")
$instances = Get-EC2Instance -Filter @($tagFilter1)
#New or update tag on instances
foreach ($i in $instances.Instances) {
	New-EC2Tag -ResourceId $i.InstanceId -Tags @(@{ Key="YourTagName"; Value="YourTagValue" })
}