External cache is not working as expected for the APIM

Hello Anand,

Thank you for reaching out to the Microsoft Q&A community.

Cause: The cache instance was created using terraform and cache ID used was a custom unique name instead of "default".

As per guidance from backend team, below steps resolved the issue. 

1. Delete the existing external cache connection
2. Re-create using the Azure Portal and make sure to select either "Default" from the drop down or select "Germany West Central".
3. If you prefer to use terraform script, you should ensure that the cache ID is "default" or specify the correct region name in "Use From".
   • Sample terraform script:

          resource "azurerm_api_management_redis_cache" "platform" {
            name              = "default" # This changes the backend cacheId to match the location
            api_management_id = azurerm_api_management.platform.id
            connection_string = "${azurerm_managed_redis.redis.hostname}:6380,password=${azurerm_managed_redis.redis.primary_access_key},ssl=True,abortConnect=False"
            description       = "Redis cache for APIM policies"
            redis_cache_id    = azurerm_managed_redis.redis.id
            cache_location    = "default"
            
            depends_on = [
              azurerm_api_management.platform,
              azurerm_managed_redis.redis,
            ]
          }