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You cannot use a dedicated service tag for Azure Cache for Redis in your Network Security Group (NSG) rules, but there are alternative approaches. The least secure option is to allow all outbound traffic from your application's subnet. A more secure method involves whitelisting specific public IP addresses used by your application, which you can find in the "Overview" section of your Azure Cache for Redis resource in the Azure portal. The most secure and recommended approach is to use Azure Private Link, which creates a private endpoint within your virtual network and avoids exposing Redis to the public internet. You can set up Azure Private Link by following the detailed instructions in the official Microsoft documentation here.
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