AZ-800 Administering Windows Server Hybrid Core Infrastructure Exam

Scope Definition and High Availability Configuration

Defining a DHCP scope starts with choosing the right IPv4 or IPv6 address range for your network. You must set up exclusion pools to keep certain addresses free from automatic assignment. Next, create reservations for devices that need fixed IP addresses, such as printers or servers. Finally, adjust lease durations so that addresses are handed out and released based on how often devices connect. Together, these settings ensure reliable IP assignment across both on-premises and Azure VM networks.

To create a new DHCP scope, follow these steps:

• Define IP address ranges within your network’s subnet.
• Configure exclusion pools for any addresses you want to reserve manually.
• Set up reservations by mapping a device’s MAC address to a fixed IP.
• Adjust lease durations to control how long devices keep their addresses.

Implementing high availability for DHCP prevents downtime if one server fails. You can use a split-scope setup, which shares a single address range across two servers, or configure a DHCP failover relationship. In a failover setup, both servers share lease information and can respond to client requests, providing continuous service even if one goes offline. This ensures devices always receive IP addresses without interruption.

In a split-scope arrangement, one server handles 80% of requests while the partner handles 20%. This method is simple to configure and offers basic redundancy. For a more robust solution, use DHCP failover, which synchronizes leases and supports modes like load balance or hot standby. Both methods keep your network running smoothly during maintenance or unexpected outages.

By defining clear scopes and setting up high availability, you maintain consistent and uninterrupted IP addressing across hybrid environments. This approach helps your organization avoid conflicts, reduce manual errors, and deliver a stable network experience for end users.

Conclusion

In this section, we explored how to define DHCP scopes by choosing address ranges, managing exclusions and reservations, and setting appropriate lease durations. We covered high-availability options, including split-scope configurations and DHCP failover relationships, to ensure continuous service during server outages. Together, these practices help maintain a reliable and efficient IP addressing system across on-premises and Azure VM networks, supporting a seamless hybrid infrastructure.