CCNP Practice Question: Is configuring OSPF on a router that has multiple…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  Set the OSPF priority to 0 on all interfaces.

  Why this is correct

  In OSPF, DR/BDR election on broadcast multi-access networks is determined by the interface priority (range 0-255). Setting the 'ip ospf priority 0' command on every local interface makes the router ineligible to ever be elected as DR or BDR, because OSPF only considers routers with a non-zero priority as candidates. This is the standard, granular way to prevent a specific router from taking that control-plane role without altering the network type or affecting other routers' eligibility.

• ✗

  Configure the OSPF network type as point-to-point on all interfaces.

  Why it's wrong here

  Configuring the OSPF network type as point-to-point on all interfaces suppresses DR/BDR election entirely by changing the design to a point-to-point link model. While this would technically prevent the local router from ever becoming DR, it is an overly broad and often incorrect fix: the question only asks to exclude this router from election, not to eliminate the election process. Additionally, point-to-point networks do not use DR/BDR but still require a separate neighbor relationship model, and applying this to non-point-to-point segments can break adjacencies and alter LSA flooding behavior.

• ✗

  Use the 'ip ospf dr-priority' command to set a high priority on other routers.

  Why it's wrong here

  Using 'ip ospf dr-priority' to assign a high priority to neighboring routers may affect who becomes DR, but it does not guarantee that the local router will be excluded unless every other router has a higher priority. Election also uses router ID as a tie-breaker; if the local router's priority is still 1 and no other candidate has a strictly higher priority, the local router could still win the election based on the RID. More importantly, this requires configuring all other routers on the segment, whereas setting the local router's own priority to 0 is a single, deterministic prevention.

• ✗

  Configure the router as an ABR.

  Why it's wrong here

  An ABR (Area Border Router) is defined by its placement between OSPF areas and its function of exchanging Type 3 summary LSAs, but DR/BDR election operates independently on each multi-access interface. ABR status does not change the interface priority or the election algorithm, so the router can still be selected as DR on a broadcast segment connected to Area 0 or a non-backbone area. Thus, configuring the router as an ABR is entirely unrelated to the goal of preventing it from becoming DR or BDR.