A critical advantage of the Standard SKU is its support for Availability Zones, which enhances infrastructure resilience. These IPs can be configured as zone-redundant, meaning they are replicated across multiple zones to survive a single zone failure, or as zonal, tied to a specific availability zone. Basic SKU IPs do not support zones and are always non-zonal resources.
Routing preference allows administrators to choose how traffic travels between Azure and the internet. The Microsoft Global Network option keeps traffic on Microsoft's high-speed fiber for as long as possible, while the Internet option exits the Microsoft network quickly to use transit ISP networks. This choice directly impacts both network performance and egress costs.
For large-scale deployments, Public IP Prefixes provide a reserved range of contiguous IP addresses, ensuring that a set of IPs is dedicated to a subscription and simplifying firewall management. Only Standard SKU static IPs can be derived from these prefixes, and benefits include predictable IP ranges for security rules, reduced management overhead during scaling, and support for both IPv4 and IPv6 stacks.
Differentiate Between Static and Dynamic Public IP Addresses
Dynamic IP addresses are assigned by default in Azure. For public IP addresses, Azure assigns the address from a range unique to each Azure region, and these addresses can change when a virtual machine is stopped and then started again. For private IP addresses, Azure reserves the first four addresses in each subnet and assigns the next available unassigned address, which can change if the network interface is deleted, assigned to a different subnet, or the allocation method is changed to static.
Static IP addresses can be optionally assigned to both public and private IP configurations. For public IP addresses, Azure assigns the address from a range unique to each region, and the address remains the same until the resource is deleted or the allocation method is changed. For private IP addresses, you select and assign an address from the subnet's range, and it remains fixed unless the network interface is deleted or reassigned.
Dynamic IP addresses are suitable for scenarios where IP stability is not critical, such as development and testing environments. Static IP addresses are ideal for production environments where consistent IP addresses are necessary for DNS settings, SSL certificates, and firewall rules. The choice between dynamic and static IP addresses depends on the specific needs of your Azure environment, and understanding these allocation methods helps ensure proper configuration and management of virtual networks.