Which Feature Programs Leaf Policy CAM Without VM Traffic?

300-620 By islever Editorial Last updated

Short answer

B Immediate deployment immediacy programs the EPG policy into the leaf policy CAM without waiting for the first packet from the VM.

Question

Which feature is used to program policy CAM on a leaf switch without sending traffic from VM to the leaf?
  1. immediate resolution immediacy
  2. immediate deployment immediacy Correct Answer
  3. on-demand deployment immediacy
  4. on-demand resolution immediacy

Key Takeaways

It tests the difference between Deployment Immediacy (when a policy is programmed into the leaf policy CAM) and Resolution Immediacy (when the policy is resolved onto the leaf); the trap is picking "immediate resolution immediacy" because resolving a policy early sounds like pre-programming hardware.

In Cisco ACI, Deployment Immediacy decides when an EPG's policy is written into the leaf switch's hardware policy CAM, and the Immediate setting does it without waiting for the first packet from a VM. This page confirms immediate deployment immediacy as the answer and separates it from the resolution-immediacy distractors.

Common mistake: The most common wrong pick is A, immediate resolution immediacy, assuming that resolving a policy early is what installs it in hardware — resolution only gets the policy down to the leaf, while deployment immediacy is what writes it into the policy CAM.

Expert Analysis

Why the Answer Is Correct

Deployment immediacy is the ACI attribute that governs when a resolved policy is actually written into the leaf switch's policy CAM (the hardware TCAM that holds EPG, VLAN, VXLAN and contract entries). Setting it to Immediate makes the APIC program the binding into leaf hardware as soon as the policy is resolved, so no frame has to arrive from the VM first. On-Demand deployment is precisely the behaviour the question excludes, because the leaf then holds the policy until the first packet is received. Because "immediate deployment immediacy" pairs the right knob (deployment) with the right value (immediate), B is the only option that satisfies "program policy CAM without sending traffic from VM to the leaf."

Why the Other Options Are Wrong

Option A, immediate resolution immediacy, confuses two separate attributes: resolution immediacy (resImedcy on the EPG-to-domain binding) controls when the policy is resolved/downloaded onto the leaf, not when a CAM entry is installed, so a policy can be resolved yet still absent from hardware until traffic arrives. Option C, on-demand deployment immediacy, is the exact reverse of the requirement — the leaf waits for the first packet before programming the CAM. Option D, on-demand resolution immediacy, is wrong on both axes, since it is neither the deployment knob nor an immediate value.

Community Comment Notes

Rollizo summarised the winning logic concisely: the policy is "Deployed in CAM without to wait the first packet," which is why the deployment attribute, not the resolution attribute, is in play. Habtamu added simply "Answer is B b/c no need traffic," matching the majority view. prospio971 argued for A, stating that "Resolution Immediacy determines when policies" such as VLANs, VXLAN bindings, contracts or filters are pushed to the leaf switches — that is a correct description of resolution, but getting a policy onto the leaf is a precondition, not the CAM programming step the question asks about.

Official Reference

https://developer.cisco.com/docs/apic-mim-ref/

This link opens the official vendor documentation in a new tab.

Exam Strategy

Separate the two immediacy axes before answering: resolution = is the policy resolved/downloaded onto the leaf, deployment = is the policy written into the leaf policy CAM. Any stem mentioning CAM, hardware programming or "without traffic/first packet" points to Deployment Immediacy, and "without traffic" rules out the On-Demand value.

Frequently Asked Questions

Why is immediate deployment immediacy needed instead of immediate resolution immediacy?

Resolution immediacy only decides whether the policy is resolved/downloaded onto the leaf, while deployment immediacy decides when that policy is actually written into the leaf's hardware policy CAM.

What happens if deployment immediacy stays on-demand?

The leaf holds the policy until the first packet arrives from an endpoint, so no CAM entry is programmed until VM traffic reaches the leaf switch.

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Community Votes

B
75%
A
25%

75% of anonymous learners picked answer B. Votes are pick records left by other test-takers — they are not the verified answer.

Discussion 3 contributions

Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.

From public community threads 3

  1. Rollizo 👍 3 Answered B
    Deployed in CAM without to wait the first packet
  2. prospio971 👍 1 Answered A
    In Cisco ACI, Resolution Immediacy determines when policies (such as VLANs, VXLAN bindings, contracts, or filters) are pushed to the leaf switches. If the goal is to program the policy CAM on a leaf switch without requiring traffic from a VM to trigger it, the correct setting is Immediate Resolution Immediacy.
  3. Habtamu 👍 1
    Answer is B b/c no need traffic

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