azure-quickstart-templates/memcached-multi-vm-ubuntu/azuredeploy-parameters.json

{
    "$schema": "http://schema.management.azure.com/schemas/2014-04-01-preview/deploymentParameters.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "adminUsername": {
            "value": "azureuser"
        }
    }
}