[Update: Solved. The culprit was a UDM SE software update that disabled ICMP echo by default that must have coincided. It looks like the provider pings my IP and occasionally resets the connection if it doesn’t get a response, just in case. Or they just started doing this, either way, I’m happy.]

Heya networking nerds: after a few weeks away from home, I came back to a UDM SE. I unplugged two POE+ cables and might have screwed something up in the process (nothing else changed afaict).

Since then, the fiber internet connection via an SFP+ module on port 10 briefly drops every few minutes (2–5). I can observe this with a continuous ping and I see a mix of high latency (10–20x), connection resets and hosts not reachable.

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