4A0-113 Exam Dumps : Nokia OSPF Routing Protocol Exam

Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (OSPF DR/BDR Election Rules):

“The router with the highest OSPF interface priority is elected DR.”

“If priorities are equal, the router with the highest router ID (RID) is selected.”

Thus:

B (Correct): Highest priority wins.

D (Correct): Highest RID used as tie-breaker.

Incorrect:

A: Lowest priority is incorrect.

C: Lowest RID is incorrect.

Correct answers: B, D.

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Comprehensive and Detailed Explanation From Exact Extract:

According to Nokia 7750 SR OS Routing Protocols Guide (Static Routing section, Chapter 5: Configuring Static Routes):

“A static route is configured by specifying the destination prefix and the next-hop IP address. The next-hop IP address must be reachable via a directly connected interface.”

In this scenario:

The network R1 wants to reach is 139.120.121.0/24 (behind R2).

R1 can reach R2 directly via IP 138.120.199.2 (the next-hop).

Therefore, the correct static route configuration on R1 is:

configure router static-route 139.120.121.0/24 next-hop 138.120.199.2

Explanation of incorrect options:

Option B: Next-hop 138.120.199.1 is R1 itself, invalid.

Option C: Configures a route to R2's interface, not the target subnet.

Option D: Next-hop 139.120.121.2 is unreachable from R1 directly.

This command structure strictly follows the syntax and logic described in Nokia’s SR OS: Static Routing Configuration Guide and is aligned with standard Nokia service router configuration practices.

Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (Router ID Selection):

“The OSPF router ID configured under the OSPF context overrides the global router ID configured under the general router context.”

Since "configure router ospf router-id 10.10.10.99" was applied, this takes precedence for OSPF operation, even though "configure router router-id 10.10.10.66" was configured globally.

Thus, router R1 will see router R2’s OSPF router ID as 10.10.10.99.

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