Azure Automation: Service Principal account from different tenant authenticates but doesn't return service principal - azure

Question

I'm having issues executing a runbook aon a subscription in a different tenant.
This is what I have done so far:
1) Created a keyvault cert.
2) Exported .cer and .PFX of certificate.
3) Created a Service Principal on the rpgorch-aad account (300eab96-4619-4b6b-af42-8eb66506ab04)
4) Created a connection in Automation with that service principal's information
5) Uploaded password protected PFX to Automation certificate store
First, a working example from within the same tenant:
$connectionName = 'AzureRunasConnection'
"Getting Azure Connection $connectionName"
$servicePrincipalConnection = Get-AutomationConnection -Name $connectionName
"Logging in to Azure using Add-AzureRmAccount"
Add-AzureRmAccount -ServicePrincipal `
-Tenant $servicePrincipalConnection.TenantID `
-ApplicationId $servicePrincipalConnection.ApplicationId `
-CertificateThumbprint $servicePrincipalConnection.CertificateThumbprint -Verbose
"Setting Context with Set-AzureRmContext"
Set-AzureRmContext -Tenant $servicePrincipalConnection.TenantID -SubscriptionId $servicePrincipalConnection.SubscriptionId -Verbose
"Writing Output of the Service Principal Connection"
write-output $servicePrincipalConnection
"Testing getting resource groups."
Get-AzureRmResourceGroup
Results:
Getting Azure Connection AzureRunasConnection
Logging in to Azure using Add-AzureRmAccount
PSComputerName : localhost
PSSourceJobInstanceId : Redacted
Environments : {AzureCloud, AzureChinaCloud, AzureUSGovernment}
Context : Microsoft.Azure.Commands.Profile.Models.PSAzureContext
Setting Context with Set-AzureRmContext
PSComputerName : localhost
PSSourceJobInstanceId : Redacted
Account : Redacted
Environment : AzureCloud
Subscription : Redacted
Tenant : Redacted
Writing Output of the Service Principal Connection
Name Value
---- -----
SubscriptionId Redacted
TenantId Redacted
ApplicationId Redacted
CertificateThumbprint Redacted
Testing getting resource groups.
PSComputerName : localhost
PSSourceJobInstanceId : Redacted
ResourceGroupName : Redacted
Location : eastus
Resources :
ResourcesTable :
ProvisioningState : Succeeded
Tags : {}
TagsTable :
ResourceId : /subscriptions/Redacted/resourceGroups/Redacted
Now the SAME code, but for the other tenant.
$connectionName = 'Redacted'
"Getting Azure Connection"
$connectionName
$Conn = Get-AutomationConnection -Name $connectionName
"Logging in to Azure using Add-AzureRmAccount"
Add-AzureRmAccount -ServicePrincipal `
-Tenant $Conn.TenantID `
-ApplicationId $Conn.ApplicationId `
-CertificateThumbprint $Conn.CertificateThumbprint -Verbose
"Setting Context with Set-AzureRmContext"
Set-AzureRmContext -Tenant $Conn.TenantID -SubscriptionId $Conn.SubscriptionId -Verbose
"Selecting subscriptionID "
$Conn.SubscriptionID
Select-AzureSubscription -SubscriptionId $Conn.SubscriptionID
"Testing getting resource groups."
Get-AzureRmResourceGroup
Results:
Getting Azure Connection
RPGOrchResourceManagement
Logging in to Azure using Add-AzureRmAccount
Results:
PSComputerName : localhost
PSSourceJobInstanceId : Redacted
Environments : {AzureCloud, AzureChinaCloud, AzureUSGovernment}
Context : Microsoft.Azure.Commands.Profile.Models.PSAzureContext
Setting Context with Set-AzureRmContext
Set-AzureRmContext : Provided subscription Redacted does not exist
At ManageSingleVM:52 char:52
+
+ CategoryInfo : CloseError: (:) [Set-AzureRmContext], ArgumentException
+ FullyQualifiedErrorId : Microsoft.Azure.Commands.Profile.SetAzureRMContextCommand
PSComputerName : localhost
PSSourceJobInstanceId : Redacted
Environments : {AzureCloud, AzureChinaCloud, AzureUSGovernment}
Context : Microsoft.Azure.Commands.Profile.Models.PSAzureContext
Setting Context with Set-AzureRmContext
Set-AzureRmContext : Provided subscription Redacted does not exist
At ManageSingleVM:52 char:52
+
+ CategoryInfo : CloseError: (:) [Set-AzureRmContext], ArgumentException
+ FullyQualifiedErrorId : Microsoft.Azure.Commands.Profile.SetAzureRMContextCommand

Answer 1

I figured out the answer to this. For anyone else looking, I needed to run this command on the Application ID:
New-AzureRMRoleAssignment -RoleDefinitionName Contributor -ServicePrincipalName $ApplicationId | Write-Verbose -ErrorAction SilentlyContinue