AZ-700 · Domain 1 of 5

AZ-700 Domain 1: Design and implement core networking infrastructure

The largest AZ-700 skill area: planning address space and subnets, public IP resources, Azure DNS and DNS Private Resolver, peering and user-defined routing, Route Server and NAT Gateway, plus monitoring with Network Watcher and Defender for Cloud.

Exam weight
25–30%
Official functional groups
4
Estimated questions estimate
~14
Suggested study time estimate
14–18 hrs

About 14 min read Reviewed October 2026

Overview

Domain 1 is the foundation every other AZ-700 skill area builds on. Microsoft splits it into four functional groups. IP addressing covers address spaces, subnet sizing for gateways, firewalls, Bastion and delegated services, public IP addresses, public IP prefixes and bring-your-own Custom IP prefixes. Name resolution covers VNet DNS settings, public and private DNS zones, virtual network links and Azure DNS Private Resolver. Connectivity and routing covers peering with gateway transit, Azure Virtual Network Manager, user-defined routes, forced tunneling, Azure Route Server and NAT Gateway.

The fourth group, Monitor networks, covers Network Watcher diagnostics and logs, Azure Monitor network insights, DDoS Protection, and the network findings surfaced by Microsoft Defender for Cloud through Secure Score, attack path analysis and Cloud Security Explorer. At 25–30% this is the heaviest domain, and AZ-700 remains an active exam with no retirement announced as of October 2026.

How it's tested

AZ-700 questions in this domain present a network diagram or a requirements list and ask which address plan, DNS design, route or diagnostic tool fits. Expect case studies, drag-and-drop ordering of configuration steps and items where two answers work but only one meets every stated constraint such as cost or least administrative effort.

  • Pick the subnet plan

    A set of services is listed, and you choose subnet names and sizes that leave room for gateways, firewalls, Bastion and delegated platform services.

  • Fix the route

    Traffic takes the wrong path, and you identify the missing or conflicting user-defined route, peering setting or BGP propagation option.

  • Choose the diagnostic

    A connectivity symptom is described, and you select the Network Watcher capability that isolates the cause fastest.

Reasoning it through

Spoke VMs must reach on-premises through a VPN gateway that lives in the hub. Peering alone does not share the gateway. The hub peering needs Allow gateway transit, and each spoke peering needs Use remote gateways. If the spokes also have their own gateway, Use remote gateways cannot be enabled. Recognizing that the requirement is shared gateway access, not more peering, points to the gateway transit settings.

Functional groups 4

Official functional groups from the Microsoft outline, in outline order.

1.1 Design and implement IP addressing for Azure resourcesAddress spaces, subnet planning, delegation, public IP addresses and prefixes.
What it means
This group covers planning non-overlapping address spaces and segmentation, creating VNets, sizing subnets for virtual network gateways, private endpoints, firewalls, application gateways, VNet-integrated platform services and Azure Bastion, choosing shared or dedicated subnets, subnet delegation, public IP addresses, public IP prefixes and Custom IP prefixes for bringing your own ranges.
What to understand
Azure reserves five addresses in every subnet, so a /29 yields three usable IPs. Several services require a dedicated, specifically named subnet: GatewaySubnet, AzureFirewallSubnet (/26), AzureBastionSubnet (/26 or larger) and RouteServerSubnet. Delegation hands a subnet to one platform service such as SQL Managed Instance or App Service VNet integration. A public IP prefix reserves a contiguous block of Standard static addresses so allow lists stay stable. A Custom IP prefix onboards a range your organization already owns.
How it shows up
Expect a list of planned services and a question about the minimum subnet size, required subnet name or whether a prefix is needed for predictable outbound addresses.
Common confusion
Thinking a public IP prefix brings your own addresses; that is a Custom IP prefix, while a public IP prefix is Microsoft-owned space.
1.2 Design and implement name resolutionAzure-provided DNS, custom DNS, public and private zones, links and DNS Private Resolver.
What it means
This group covers how VMs in a VNet resolve names, configuring DNS server settings on the VNet, designing and configuring public DNS zones and private DNS zones, linking a private zone to VNets with optional autoregistration, and designing Azure DNS Private Resolver for hybrid resolution between Azure and on-premises.
What to understand
By default a VNet uses Azure-provided DNS at 168.63.129.16. Setting custom DNS servers on the VNet changes every NIC unless overridden. A private DNS zone resolves only for VNets that have a virtual network link to it, and autoregistration creates records for VMs in that VNet. DNS Private Resolver uses an inbound endpoint so on-premises servers can forward queries into Azure, and an outbound endpoint with a forwarding ruleset so Azure workloads can resolve on-premises domains, removing the need for DNS server VMs.
How it shows up
Expect hybrid scenarios that ask which resolver endpoint, ruleset or zone link lets a specific client resolve a specific name.
Common confusion
Mixing up inbound and outbound endpoints; inbound receives queries from on-premises, outbound sends Azure queries to external DNS servers.
1.3 Design and implement VNet connectivity and routingPeering, gateway transit, Virtual Network Manager, UDRs, forced tunneling, Route Server and NAT Gateway.
What it means
This group covers designing service chaining and gateway transit, implementing regional and global VNet peering, managing connectivity at scale with Azure Virtual Network Manager, creating user-defined routes and associating route tables with subnets, forced tunneling, diagnosing routing problems, deploying Azure Route Server for BGP with network virtual appliances, and choosing and implementing Azure NAT Gateway.
What to understand
Peering is not transitive, so spoke-to-spoke traffic needs a hub appliance with UDRs, direct peering or a Virtual Network Manager mesh. Azure picks the route with the longest matching prefix, then prefers user-defined over BGP over system routes. Forced tunneling sends 0.0.0.0/0 to on-premises for inspection. Route Server exchanges routes with NVAs over BGP but never carries data traffic. NAT Gateway gives a subnet scalable outbound SNAT and takes priority over load balancer outbound rules and default outbound access.
How it shows up
Expect questions about why two spokes cannot talk, which next hop type to use, or what to deploy so NVA routes reach VNets automatically.
Common confusion
Assuming Route Server forwards packets; it only exchanges routes, and traffic still flows directly to the NVA.
1.4 Monitor networksNetwork Watcher, Azure Monitor network insights, DDoS Protection and Defender for Cloud findings.
What it means
This group covers configuring Network Watcher monitoring, diagnostics and logs, troubleshooting network health with Network Watcher and with Azure Monitor network insights, enabling and monitoring DDoS protection, and evaluating network recommendations from Microsoft Defender for Cloud through Secure Score, attack path analysis and Cloud Security Explorer.
What to understand
Network Watcher tools each answer one question: IP flow verify tests an NSG decision, next hop shows the chosen route, connection troubleshoot tests end-to-end reachability, Connection monitor tracks latency and loss over time, and packet capture records traffic. Virtual network flow logs with traffic analytics replace NSG flow logs. DDoS Network Protection covers a whole VNet with cost protection and rapid response support, while DDoS IP Protection is priced per public IP. Defender for Cloud ranks exposures such as internet-facing VMs and shows exploitable attack paths.
How it shows up
Expect a symptom followed by four Network Watcher tools, or a request to find all internet-exposed VMs across subscriptions.
Common confusion
Using IP flow verify to find routing problems; it only evaluates NSG rules, while next hop reveals the effective route.

High-yield concepts

The terms, rules and formulas this domain turns into questions most often.

  • Five reserved subnet addresses

    Azure keeps the network, gateway, two DNS-mapped and broadcast addresses in every subnet.

    Remember
    Usable hosts equal the subnet size minus five.
    Tested as
    Subnet sizing questions.
    Trap
    Subtracting only two addresses as in traditional networking.
  • GatewaySubnet

    The required subnet name for VPN and ExpressRoute gateways.

    Remember
    Use /27 or larger and never attach an NSG that blocks gateway traffic.
    Tested as
    Gateway deployment questions.
    Trap
    Renaming it or sizing it at /29 for a coexistence design.
  • Subnet delegation

    Assigning a subnet to one Azure platform service so it can inject resources there.

    Remember
    A delegated subnet serves only that service.
    Tested as
    Subnet planning questions.
    Trap
    Placing VMs in a delegated subnet.
  • Public IP prefix vs Custom IP prefix

    A prefix reserves contiguous Microsoft-owned addresses; a Custom IP prefix onboards addresses you own.

    Remember
    Both give predictable outbound and inbound addresses.
    Tested as
    IP planning and allow-list questions.
    Trap
    Treating them as the same feature.
  • Private DNS zone link

    A virtual network link that lets a VNet resolve records in a private zone.

    Remember
    Autoregistration is optional and limited to one registration zone per VNet.
    Tested as
    Name resolution questions.
    Trap
    Expecting resolution without a link.
  • DNS Private Resolver endpoints

    Inbound accepts queries from on-premises; outbound plus a ruleset forwards Azure queries out.

    Remember
    Each endpoint needs its own delegated subnet.
    Tested as
    Hybrid DNS questions.
    Trap
    Reversing inbound and outbound roles.
  • Gateway transit

    Lets peered spokes use the hub's VPN or ExpressRoute gateway.

    Remember
    Allow gateway transit on the hub, Use remote gateways on the spoke.
    Tested as
    Hub-and-spoke questions.
    Trap
    Enabling it on only one side.
  • Route selection order

    Longest prefix match first, then UDR over BGP over system routes.

    Remember
    A /24 UDR beats a 0.0.0.0/0 BGP route for its range.
    Tested as
    Routing troubleshooting questions.
    Trap
    Thinking UDR always wins regardless of prefix length.
  • Azure Route Server

    A managed BGP peer that exchanges routes between NVAs and the VNet.

    Remember
    It is control plane only and needs RouteServerSubnet.
    Tested as
    NVA integration questions.
    Trap
    Expecting traffic to pass through it.
  • NAT Gateway

    Subnet-level outbound SNAT using Standard public IPs or prefixes.

    Remember
    It overrides other outbound methods for that subnet.
    Tested as
    Outbound connectivity questions.
    Trap
    Expecting it to allow inbound connections.
  • Azure Virtual Network Manager

    Central management of connectivity, routing and security admin rules across VNets and subscriptions.

    Remember
    Network groups can be static or built dynamically with Azure Policy.
    Tested as
    Scale connectivity questions.
    Trap
    Building dozens of peerings by hand.
  • Network Watcher diagnostics

    IP flow verify, next hop, connection troubleshoot, Connection monitor and packet capture.

    Remember
    Match the tool to the symptom.
    Tested as
    Monitoring questions.
    Trap
    Choosing a tool that inspects the wrong layer.
  • Virtual network flow logs

    Flow logging at VNet scope that replaces NSG flow logs.

    Remember
    Pair with traffic analytics for insight.
    Tested as
    Logging questions.
    Trap
    Planning new NSG flow logs.

Side by side

Concepts candidates mix up, compared on the point that decides the answer.

Routing components

ConceptMeaningKey differenceCommon trap
User-defined route Static route in a route table on a subnet Manual, you set the next hop Forgetting to associate the table
BGP routes Learned from gateways or Route Server Dynamic, can be suppressed per route table Ignoring BGP propagation settings
System routes Default routes Azure creates Lowest preference at equal prefix Assuming they can be deleted
Azure Route Server BGP peer for NVAs Exchanges routes, never forwards packets Placing it in the data path

Network Watcher tools

ConceptMeaningKey differenceCommon trap
IP flow verify Tests if an NSG allows a 5-tuple NSG decision only Using it for route issues
Next hop Shows the route chosen for a destination Routing only Using it for NSG issues
Connection troubleshoot Tests reachability from a source to a destination End-to-end check at one point in time Expecting ongoing trends
Connection monitor Continuous latency and loss tracking Ongoing monitoring with alerts Using it for a one-off check

DNS Private Resolver parts

ConceptMeaningKey differenceCommon trap
Inbound endpoint Private IP that on-premises DNS forwards to Traffic into Azure DNS Using it for outbound forwarding
Outbound endpoint Egress point for Azure queries Traffic from Azure outward Forgetting the ruleset
Forwarding ruleset Domain rules that send queries to target DNS servers Linked to VNets Not linking it to the spoke VNets

Exam traps

Each trap is an answer that looks right. Learn the clue that should change your mind.

  1. Peering is transitive

    What candidates pick
    Peer both spokes to the hub and expect spoke-to-spoke traffic.
    Why it looks right
    Hub-and-spoke diagrams look connected.
    Why it's wrong
    Peering connects only the two VNets in the pair, so spoke traffic needs an NVA or firewall with UDRs, direct peering or a managed mesh.

    Clue to watch for Two spokes are peered only with the hub.

  2. Prefix means BYOIP

    What candidates pick
    Choose a public IP prefix to use company-owned addresses.
    Why it looks right
    Both features contain the word prefix.
    Why it's wrong
    A public IP prefix allocates Microsoft-owned addresses; owned ranges require a Custom IP prefix onboarding process.

    Clue to watch for The organization already owns the IP range.

  3. Route Server in the path

    What candidates pick
    Send traffic to Route Server as a next hop.
    Why it looks right
    It sounds like a router.
    Why it's wrong
    Route Server only exchanges BGP routes; packets go directly to the NVA it advertised.

    Clue to watch for The scenario needs NVA routes learned automatically.

  4. UDR always wins

    What candidates pick
    Assume a user-defined route beats any learned route.
    Why it looks right
    UDR has the highest preference.
    Why it's wrong
    Preference applies only at equal prefix length; a more specific BGP or system route still wins.

    Clue to watch for Route prefixes of different lengths overlap.

  5. Outbound needs a load balancer

    What candidates pick
    Add a public load balancer with outbound rules for subnet egress.
    Why it looks right
    Outbound rules are familiar from older designs.
    Why it's wrong
    NAT Gateway gives scalable outbound SNAT for a whole subnet with less configuration and takes precedence over load balancer outbound rules.

    Clue to watch for Requirement mentions SNAT exhaustion or many outbound connections.

  6. Resolver without links

    What candidates pick
    Deploy DNS Private Resolver and expect spokes to use forwarding rules.
    Why it looks right
    The resolver lives in the hub.
    Why it's wrong
    A forwarding ruleset applies only to VNets linked to it, so each spoke needs a ruleset link or DNS settings pointing at the hub.

    Clue to watch for Spoke VMs cannot resolve on-premises names.

Answer framework

Use these steps to work through a Domain 1 infrastructure scenario on AZ-700.

  1. Start with addressing: confirm the address spaces do not overlap with peers or on-premises, and size each subnet after removing the five reserved addresses.
  2. List services that demand dedicated or named subnets, such as gateways, firewalls, Bastion, Route Server and delegated platform services, and reserve those first.
  3. Decide how names resolve: Azure-provided DNS, custom servers, private zones with links, or DNS Private Resolver endpoints for hybrid queries.
  4. Trace each traffic path, checking peering settings, gateway transit, user-defined routes, BGP propagation and longest prefix match, and pick NAT Gateway for subnet egress.
  5. For any failure, choose the narrowest Network Watcher tool or Defender for Cloud view that proves the cause.

Practice question

A company has a hub VNet with an Azure Firewall and two spoke VNets peered only with the hub. Workloads in Spoke1 cannot reach workloads in Spoke2. Security requires all spoke-to-spoke traffic to be inspected. What should you configure?

Choose one answer

Want more like this? The AZ-700 practice test has questions for every domain.

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Study strategy

Start this domain in a lab subscription, because the concepts stick far better once you have watched a peering fail to carry spoke traffic. Build a hub and two spokes, add a small VM in each, and test reachability. Then add a route table, change next hops, and watch the effective routes on a NIC. Size every subnet deliberately and write down which services need named subnets.

Next, work on DNS. Create a private DNS zone, link it with and without autoregistration, and point a VNet at custom DNS servers to see the effect. Read the DNS Private Resolver architecture until you can explain both endpoints and the ruleset from memory.

Finish with monitoring. Run IP flow verify, next hop and connection troubleshoot against the lab, enable virtual network flow logs, and open the Defender for Cloud network recommendations. Because this domain is up to 30% of the exam and feeds every other domain, revisit it after you study connectivity and security, then take timed practice sets focused on routing and DNS.

FAQ

How much of AZ-700 is Domain 1, Design and implement core networking infrastructure?

Microsoft weights it at 25–30%, the largest of the five skill areas, with four functional groups covering addressing, name resolution, routing and monitoring.

Is VNet peering transitive?

No. Each peering connects only two VNets. Spoke-to-spoke traffic needs a hub NVA or firewall with user-defined routes, a direct peering, or a mesh built with Azure Virtual Network Manager.

What is the difference between Azure Route Server and a user-defined route?

A UDR is a static route you write in a route table. Route Server learns routes from NVAs over BGP and programs them into the VNet automatically.

When should I use NAT Gateway?

Use it when a subnet needs reliable, scalable outbound internet access with fixed public IPs, especially when SNAT port exhaustion is a risk.

What does Azure DNS Private Resolver replace?

It replaces custom DNS forwarder VMs for hybrid resolution, offering managed inbound and outbound endpoints and forwarding rulesets.

Which Network Watcher tool shows why traffic goes to the wrong place?

Next hop shows the route Azure selects for a destination from a VM, including the next hop type and route table responsible.

Is AZ-700 being retired?

No retirement had been announced as of October 2026. The current study guide lists skills measured as of July 27, 2026.

Other Networking certifications

Where the same subject shows up in other exams. Cards marked "Same subject" open the matching domain.

Test your Domain 1 knowledge

You have reviewed addressing, DNS, peering, routing, NAT Gateway and network monitoring. Check whether you can trace a packet and pick the right fix under timed conditions.

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