All symptoms are the same as several months ago Renew certificate failed due to secondary validation Letsencrypt validation servers could not connect to the web server at Hetzner (DE) network: Domain: mydomain.com Type: connection Detail: During secondary validation: my.ip.address: Fetching …

[image] Bruce5051: Then please address the Let's Encrypt staff. How and/or where? [image] harrycranston53: I expect Hetzner has far more resources that LE to handle these types of issues. Hetzner do not block incoming traffic. If some internet server1 (LE) has connection problem with…

Seem a bit simplistic in today's Internet, you solution looks fine before Internet worm of November 2, 1988 Morris worm - Wikipedia , but with all the firewalls and specific ports being blocked and routed in various ways it take more than a simple traceroute. Also Hetzner seems to be a pay for servi…

[image] harrycranston53: Seem a bit simplistic in today's Internet ping and traceroute as first diagnosis for the connection related issues are still actual in 2022. In any case network support staff can use various tools. I do not think this is subject of this thread.

[image] smon: In any case network support staff can use various tools. So Hetzner should be able to the work as well.

[image] harrycranston53: So Hetzner should be able to the work as well. Friend! It seems you are excessively optimistic if you know how to diagnose on the provider level the client issue like "some server (I do not know its IP) can not connect to my server at you. Please tell me what the prob…

[image] harrycranston53: What exactly is the specific point of this topic? Some LE validation server(s) can not connect to the server requesting certificate. This issue does not relate to the requesting server because it has no limitations for the connections.

Perhaps it's not a specific firewall rule per se, but a MSS/MTU issue due to Minor change to validation networking ?

[image] Osiris: but a MSS/MTU issue due to Thank you! Those changes was in July, 2022 But I faced this issue in May, 2022. Moreover, this issue is related to only some (not all) LE validation servers. Most of LE servers successfully connect to my server, but some - not. I do not know how…

[image] smon: I do not know how they works but I geuss that "connection error" in the log actually may be some other type of error on the LE validation server internal software. I'm not sure if the error can be more specific than "Timeout during connect (likely firewall problem)".

Renew certificate failed due to secondary validation (again)

Help

harrycranston53 September 29, 2022, 8:35pm 26

What exactly is the specific point of this topic?
You seem to have solved your problem previously, just repeat the same actions.

Topic		Replies	Views
Renew certificate failed due to secondary validation Help	31	2745	June 2, 2022
Error getting validation data Help	13	623	December 28, 2025
Yet another "Timeout" while verifying via HTTP Help	25	3523	June 17, 2021
Can't renew with certbot or Crypt::LE, Timeout during secondary validation (403 resolved) Help	80	2767	May 1, 2024
HTTPS connection failures (timeouts) from validation servers Help	35	1134	December 14, 2025

Renew certificate failed due to secondary validation (again)

Related topics