nerdexam
Cisco

300-320 · Question #289

Which action can be taken on a multiaccess segment with OSPF speakers to reduce the performance impact during widespread convergence events?

The correct answer is B. Enable LSA throttling in the core to slow link state advertisement updates during times of network. "It is worth noting that three most important timers to tune network for sub-second convergence are the failure detection delay, initial LSA generation delay and initial SPF delay. All other timers, such as hold and maximum time serve the purpose of stabilizing network, and…

Advanced Addressing and Routing Solutions

Question

Which action can be taken on a multiaccess segment with OSPF speakers to reduce the performance impact during widespread convergence events?

Options

  • ASeparate the network into multiple areas for each new multiaccess segment.
  • BEnable LSA throttling in the core to slow link state advertisement updates during times of network
  • CEnsure that the elected DR or BDR router can support high-volume convergence events.
  • DVerify that fewer than 50 OSPF speakers are on the segment.

How the community answered

(40 responses)
  • A
    3% (1)
  • B
    78% (31)
  • C
    13% (5)
  • D
    8% (3)

Explanation

"It is worth noting that three most important timers to tune network for sub-second convergence are the failure detection delay, initial LSA generation delay and initial SPF delay. All other timers, such as hold and maximum time serve the purpose of stabilizing network, and affect convergence in "worst-case" unstable network scenarios." More info on LSA throttling: "Benefits of OSPF LSA Throttling Prior to the OSPF LSA Throttling feature, LSA generation was rate-limited for 5 seconds. That meant that changes in an LSA could not be propagated in milliseconds, so the OSPF network could not achieve millisecond convergence. The OSPF LSA Throttling feature is enabled by default and allows faster OSPF convergence (in milliseconds). This feature can be customized. One command controls the generation (sending) of LSAs and another command controls the receiving interval. This feature also provides a dynamic mechanism to slow down the frequency of LSA updates in OSPF during times of network

Topics

#OSPF#LSA throttling#convergence optimization#multiaccess segment

Community Discussion

No community discussion yet for this question.

Full 300-320 Practice