# Arista EOS Spooky Action at a Distance

DevFeed: [Arista EOS Spooky Action at a Distance](<https://devfeed.tech/articles/arista-eos-spooky-action-at-a-distance-11147.md>)

Original publisher: [Read original article](<https://blog.ipspace.net/2025/03/arista-spooky-action-distance/>)

Published: 2025-03-17T08:10:00Z

Content type: article

Language: en

Sources: [ipSpace.net blog](<https://devfeed.tech/sources/ipspace-net-blog.md>)

Topics: [Integration testing](<https://devfeed.tech/topics/integration-testing.md>), [Ethernet](<https://devfeed.tech/topics/ethernet.md>), [qemu](<https://devfeed.tech/topics/qemu.md>), [Linux](<https://devfeed.tech/topics/linux.md>), [JSON](<https://devfeed.tech/topics/json.md>)

Tags: [blog](<https://devfeed.tech/tags/blog.md>), [blog-post](<https://devfeed.tech/tags/blog-post.md>), [ethernet](<https://devfeed.tech/tags/ethernet.md>), [integration-testing](<https://devfeed.tech/tags/integration-testing.md>), [ipv4](<https://devfeed.tech/tags/ipv4.md>), [json](<https://devfeed.tech/tags/json.md>), [lan](<https://devfeed.tech/tags/lan.md>), [linux](<https://devfeed.tech/tags/linux.md>), [netlab](<https://devfeed.tech/tags/netlab.md>), [qemu](<https://devfeed.tech/tags/qemu.md>), [testing](<https://devfeed.tech/tags/testing.md>), [tests](<https://devfeed.tech/tags/tests.md>), [validation](<https://devfeed.tech/tags/validation.md>), [virtualization](<https://devfeed.tech/tags/virtualization.md>)

## AI overview

This blog post investigates unexpected Arista EOS behavior found during netlab VRRP integration testing. In a minimal lab, shutting down one switch interface caused the other switch's Ethernet line protocol to go down and stopped responses from the VRRP backup. Packet capture indicated that the first switch sent a packet instructing the peer to emulate remote link loss.

## Source excerpt

This blog post describes yet another bizarre behavior discovered during the netlab integration testing. It started innocently enough: I was working on the VRRP integration test and wanted to use Arista EOS as the second (probe) device in the VRRP cluster because it produces nice JSON-formatted results that are easy to use in validation tests. Everything looked great until I ran the test on all platforms on which netlab configures VRRP, and all of them passed apart from Arista EOS (that was before we figured out how Sturgeon's Law applies to VRRPv3) - a "That's funny" moment that was directly responsible for me wasting a few hours chasing white rabbits down this trail. Read more ...