AZ-800 Azure Route Tables and User-Defined Routes 1 — Questions and Answers
Question 1: What is the primary purpose of User-Defined Routes (UDRs) in Azure Virtual Networks?
- To override Azure's default system routes and control traffic flow (Correct answer)
- To automatically assign IP addresses to virtual machines
- To configure DNS settings for virtual networks
- To enable peering between virtual networks in different regions
Correct answer: To override Azure's default system routes and control traffic flow
UDRs allow administrators to override Azure's default system routes to precisely control how traffic is routed within and out of a VNet.
Question 2: Which next hop type is used in a UDR to send traffic to an Azure Firewall or Network Virtual Appliance (NVA)?
- Internet
- VirtualNetworkGateway
- VirtualAppliance (Correct answer)
- VirtualNetwork
Correct answer: VirtualAppliance
The VirtualAppliance next hop type routes traffic to a specific private IP address, typically an NVA or Azure Firewall instance.
Question 3: How many route tables can be associated with a single subnet at one time?
- Unlimited
- One (Correct answer)
- Two
- Five
Correct answer: One
Only one route table can be associated with a subnet at a time, though the same route table may be associated with multiple subnets.
Question 4: When Azure selects a route for outbound traffic and multiple routes match, what algorithm does it use?
- Highest metric value wins
- Longest prefix match — the most specific route is selected (Correct answer)
- The route created most recently is selected
- The route with the shortest name is selected
Correct answer: Longest prefix match — the most specific route is selected
Azure uses longest prefix match, selecting the most specific (longest subnet mask) route that matches the destination IP address.
Question 5: What happens when a UDR has the same address prefix as an existing Azure system route?
- The system route always takes precedence
- The UDR takes precedence over the system route (Correct answer)
- Traffic is load-balanced between both routes
- An error occurs and neither route is applied
Correct answer: The UDR takes precedence over the system route
UDRs take precedence over system routes with the same address prefix, allowing administrators to intentionally override default Azure routing behavior.
Question 6: Which PowerShell cmdlet is used to create a new route table resource in Azure?
- New-AzRouteTable (Correct answer)
- Add-AzRoute
- Set-AzRouteConfig
- New-AzNetworkRoute
Correct answer: New-AzRouteTable
New-AzRouteTable creates a new route table resource in Azure, following the standard Verb-AzNoun PowerShell naming convention.
Question 7: Which next hop type in a UDR is used to silently drop (blackhole) matched traffic?
- Internet
- None (Correct answer)
- VirtualNetwork
- VirtualAppliance
Correct answer: None
The None next hop type discards all traffic matching the route prefix, effectively creating a blackhole to block unwanted traffic.
AZ-800 Azure Route Tables and User-Defined Routes 1
What is the primary purpose of User-Defined Routes (UDRs) in Azure Virtual Networks?