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Zorluk: OrtaConfigure User-Defined Routes and Routing Tables

Your company has an Azure virtual network named `VNet-Production` (10.10.0.0/1610.10.0.0/16) that contains the following subnets:

* `FrontendSubnet` (10.10.10.0/2410.10.10.0/24)
* `SecureAppSubnet` (10.10.20.0/2410.10.20.0/24)
* `DMZSubnet` (10.10.99.0/2410.10.99.0/24)

A Network Virtual Appliance (NVA) is deployed in `DMZSubnet` and has an IP address of 10.10.99.410.10.99.4.

A route table is associated with `FrontendSubnet` and contains the following route:

* Route name: `To-NVA`
* Destination IP address/CIDR: 10.10.20.0/2410.10.20.0/24
* Next hop type: `Virtual appliance`
* Next hop IP address: 10.10.99.410.10.99.4

A user attempts to send traffic from a virtual machine in `FrontendSubnet` to a database server at 10.10.20.5510.10.20.55 in `SecureAppSubnet`.

Which two statements correctly describe how Azure routes this traffic based on prefix match and UDR override rules? (Select TWO.)

  1. Azure will select the route with the destination prefix 10.10.20.0/2410.10.20.0/24 for traffic destined to 10.10.20.5510.10.20.55 because it is the longest prefix match (LPM).Cevap
  2. The user-defined route for 10.10.20.0/2410.10.20.0/24 overrides the default system VNet local route for that subnet range because user-defined routes take precedence over system routes.Cevap
  3. C
    Azure will route the traffic using the default system local VNet route for 10.10.0.0/1610.10.0.0/16 because system routes always take precedence over user-defined routes.
  4. D
    Azure will discard the traffic because next-hop IP addresses for virtual appliances must be in the destination subnet rather than a transit subnet.

Cevap

Azure will route the traffic using the user-defined route with the destination prefix 10.10.20.0/2410.10.20.0/24 because it is the longest prefix match for 10.10.20.5510.10.20.55, and user-defined routes override the default system local virtual network routes.
Azure uses the Longest Prefix Match (LPM) algorithm to choose the route for a packet. Because the target IP address is 10.10.20.5510.10.20.55, the route for 10.10.20.0/2410.10.20.0/24 is a longer prefix match than the default system route of 10.10.0.0/1610.10.0.0/16. Furthermore, User-Defined Routes take precedence over default system routes, ensuring the packet is correctly sent to the NVA rather than routed locally.

Adım Adım Çözüm

1
Identify the destination IP and matching prefixes.
The target IP is 10.10.20.5510.10.20.55. The matching routes are the VNet local system route (10.10.0.0/1610.10.0.0/16) and the user-defined route (10.10.20.0/2410.10.20.0/24).
This establishes the candidates for routing evaluation.
2
Apply the Longest Prefix Match (LPM) rule.
The prefix 10.10.20.0/2410.10.20.0/24 is longer and more specific than 10.10.0.0/1610.10.0.0/16.
LPM is the primary rule Azure uses to determine route selection among overlapping prefixes.
3
Evaluate UDR versus system route precedence.
The UDR (10.10.20.0/2410.10.20.0/24) takes precedence over the default VNet local system route.
UDRs allow administrators to override system routes to redirect traffic (e.g., through an NVA).

Anahtar Kavram

Azure routes traffic based on the longest prefix match (LPM) first, and when prefixes match, User-Defined Routes (UDRs) override system routes.
Bu soruyu puanla

Konular

Configure User-Defined Routes and Routing Tables