Any AWS Powershell command fails with message "Invalid URI: The hostname could not be parsed."

Question

I am using powershell to create a new EC2 KeyPair using the script below:

Import-Module AWSPowerShell
$Region = "EU West"
$ProfileName = "AWS Default"
Initialize-AWSDefaults -ProfileName $ProfileName
$KeyName = "SecurityEssentials"
$KeyPair = New-EC2KeyPair -KeyName $KeyName 

However it fails on the last line with the following message:

New-EC2KeyPair : Invalid URI: The hostname could not be parsed. At C:\Users\John\Documents\Cloud\AWS Setup.ps1:12 char:12 + $KeyPair = New-EC2KeyPair -KeyName $KeyName + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidOperation: (Amazon.PowerShe...C2KeyPairCmdlet:NewEC2KeyPairCmdlet) [New-EC2KeyPair], InvalidOperationException + FullyQualifiedErrorId : System.UriFormatException,Amazon.PowerShell.Cmdlets.EC2.NewEC2KeyPairCmdlet

Using the debug flag does not provide any new information. I am using Windows 8.1 with the latest AWS SDK and AWS powershell cmdlet

Edit: The problem appears to be with the way the AWSDefaults are set up. It turns out that any command issued after this gives the same error.

Answer 1

This error Invalid URI: The hostname could not be parsed. can occur when you specify your region incorrectly. In your case, you appear to be specifying "EU West" incorrectly -- it should be eu-west-1 instead.

For example, if I use "EU West" as my region for Get-EC2Instances in a session that is otherwise correctly configured, I will get the same error:

PS C:\> get-ec2instance -Region "EU West"
get-ec2instance : Invalid URI: The hostname could not be parsed.
At line:1 char:1
+ get-ec2instance -Region "EU West"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (Amazon.PowerShe...2InstanceCmdlet:GetEC2InstanceCmdlet) [Get-EC2Insta
   nce], InvalidOperationException
    + FullyQualifiedErrorId : System.UriFormatException,Amazon.PowerShell.Cmdlets.EC2.GetEC2InstanceCmdlet

To list available AWS regions from Powershell, you can use Get-AWSRegion. Here's an example where my shell default is us-east-1:

PS C:\> Get-AWSRegion

Region         Name                      IsShellDefault
------         ----                      --------------
us-east-1      US East (Virginia)                  True
us-west-1      US West (N. California)            False
us-west-2      US West (Oregon)                   False
eu-west-1      EU West (Ireland)                  False
eu-central-1   EU Central (Frankfurt)             False
ap-northeast-1 Asia Pacific (Tokyo)               False
ap-southeast-1 Asia Pacific (Singapore)           False
ap-southeast-2 Asia Pacific (Sydney)              False
sa-east-1      South America (Sao Paulo)          False

So here we see that EU West is infact a region, but it is specified as eu-west-1 instead of EU West. So just refer to EU West as eu-west-1 and you should be able to set your defaults.

You can explicitly set which region you want to use in Initialize-AWSDefaults:

Initialize-AWSDefaults -ProfileName MyProfileName -Region eu-west-1

More info on specifying AWS regions can be found in the documentation.