For what it's worth, this doesn't look like an issue with the NAT probe test. I've attached a graph of the snowflake polling metrics for the last few hours. When the probe test fails, we see a very gradual drop in the number of known NAT types and a rise in unknown NAT types. Here, we see a sudden drop in restricted NAT types but no corresponding rise in unknowns. This may indicate an issue with proxies, or an issue with the broker reporting these metrics, or it could be some natural periodic behaviour.

On 2022-02-26 15:00, alertmanager@hetzner-nbg1-02.torproject.org wrote:

Total firing alerts: 1 Total resolved alerts: 0

## Firing Alerts

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Time: 2022-02-26 20:00:00.286335746 +0000 UTC Summary: There is a problem testing the type of NAT of our proxies Description: There are only 1.8 times proxies with known NAT type than with unknown

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##Resolved Alerts

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anti-censorship-alerts mailing list anti-censorship-alerts@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/anti-censorship-alerts