How to prepend resource group name to redis name without breaking ARM template?

Question

I am trying to deploy Redis by the means of an ARM template and to keep the Redis hostname unique, I prepend the resource group name to it with:

"variables": {
    "resourceName": "[concat(resourceGroup().id, '-', parameters('redisCacheName'))]"
},

However I suddenly get the following error, searching for which gives wildly different answers:

Deployment template validation failed: 'The template resource '/subscriptions/XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXX/resourceGroups/my-group-my-redis' for type 'Microsoft.WindowsAzure.ResourceStack.Frontdoor.Common.Entities.TemplateGenericProperty`1[System.String]' at line '1' and column '640' has incorrect segment lengths.

A nested resource type must have identical number of segments as its resource name. A root resource type must have segment length one greater than its resource name. Please see https://aka.ms/arm-template/#resources for usage details.'.

I do not understand why some "Frontdoor" is mentioned, when I am trying to deploy a Basic Redis instance and what is please the fix here?

Below is my ARM template:

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "redisCacheName": {
            "defaultValue": "my-redis",
            "type": "String"
        }
    },
    "variables": {
        "resourceName": "[concat(resourceGroup().id, '-', parameters('redisCacheName'))]"
    },
    "outputs": {
      "RedisCacheEndpoint": {
        "type": "string",
        "value": "[concat(reference(variables('resourceName')).hostName, ':', reference(variables('resourceName')).sslPort)]"
      },
      "RedisCachePassword": {
        "type": "string",
        "value": "[reference(variables('resourceName')).accessKeys.primaryKey]"
      }
    },
    "resources": [
        {
            "type": "Microsoft.Cache/Redis",
            "apiVersion": "2019-07-01",
            "name": "[variables('resourceName')]",
            "location": "[resourceGroup().location]",
            "properties": {
                "sku": {
                    "name": "Basic",
                    "family": "C",
                    "capacity": 1
                },
                "enableNonSslPort": false
            }
        }
    ]
}

And here is the parameters file:

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentParameters.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "redisCacheName": {
            "value": "my-redis"
        }
    }
}

I am trying to deploy the Redis instance into my RG called "my-group" and while deploying I use the parameter value "my-redis" -

while hoping to have a Redis endpoint with the unique name "my-group-my-redis.redis.cache.windows.net:6380" at the end.

4c74356b41 4c74356b41 · Accepted Answer · 2020-05-07T17:31:26

you are using a wrong method, you should use this:

 "[concat(resourceGroup().name, '-', parameters('redisCacheName'))]"

How to prepend resource group name to redis name without breaking ARM template?

1 Answers