Error 400 - return code:400 Details: Timeout during connect (likely firewall problem)

Hello, I use ISPmanager Lite 5.173.0 to support all my sites, so some days ago I saw that my certificates doesn’t renew and I think the problem is in my iptables, so some yours service ip’s are in my firewall list.
Can you give me the list of ip’s you use to help to solve my problem? Big thanks

My domain is:

I ran this command:

It produced this output:

My web server is (include version):

The operating system my web server runs on is (include version):

My hosting provider, if applicable, is: Rostelecom

I can login to a root shell on my machine (yes or no, or I don’t know):

I’m using a control panel to manage my site (no, or provide the name and version of the control panel): ISPmanager Lite 5.173.0

Hi @sashKO

such a list doesn't exist.

What IP addresses does Let’s Encrypt use to validate my web server?

We don’t publish a list of IP addresses we use to validate, because they may change at any time. In the future we may validate from multiple IP addresses at once.

So you must allow global access to your port 80.

But you can restrict the access to /.well-known/acme-challenge.

There is no access to / required.


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