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mediumswitching~40 min

The link bundle won't come up

Two links between switches should be one LACP port-channel, but a config mismatch keeps it down. Fix it so the bundle forms.

Scenario

Two switches, sw1 and sw2, are cabled together with two links that are supposed to bond into a single LACP port-channel for bandwidth and redundancy. But the bundle is down: the two sides don't agree, so the links aren't bundling.

Topology

  • sw1 ↔ sw2 with two links (Ethernet1 and Ethernet2 on each), meant to be Port-Channel1 via LACP.

Your job

Fix the configuration so both links bundle into Port-Channel1 and LACP negotiates with the neighbor.

What "done" looks like

show port-channel 1 shows Po1 up with both members bundled, and LACP has a neighbor on each link.

Teaches: link aggregation with LACP: both ends must use the same channel-group and an LACP mode that actually negotiates (active/passive, not one side static "on").

Tooling

Arista cEOS. Validate syntax on first deploy.

What gets checked

Your solution is verified against each of these:

  • Port-Channel1 is up with both physical links bundled
  • LACP is negotiated with the neighbor on both member links

Solve it in your browser

No setup, no install. Write your solution in the editor and hit Check. The in-house engine renders and grades it instantly, then issues your proof the moment every check passes.

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Prefer your own lab?

  1. Build the fix locally. New to the tooling? See setting up your lab.
  2. Push your topology file, device configs, and any playbooks to a public repo (GitHub or GitLab).
  3. Submit the repo link. We review it by hand, confirm it works, and issue your proof page.
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