I received the following email. Could you please let me know how I can test this or verify if my server had any issues related to this. Kindly update if any changes are needed to be made on my centos and ubuntu servers.
Starting Feb. 19, 2020, Let’s Encrypt began making multiple domain validation
requests from diverse network vantage points. More info here:
We are excited to be able to turn on this feature with little to no
interference with your integration. We expect this feature to affect less than
1% of all domain validations from the Let’s Encrypt certificate authority.
That’s better security, by default, for you and your customers.
Your ACME account ID may have some errors and failed validations
due to the multiple vantage point validation feature. We suggest you monitor
your implementation when the feature is turned on and make any fixes necessary.
In case you’re having trouble locating your affected system(s): your ACME
account recently requested a certificate on 2019-12-31 2020-01-21 for:
The best way to test compatibility for this feature is to perform test
issuances in our staging environment where the new requirement is already
If you need extra time to work on getting your integration ready for multiple
vantage point validation, we will have an exception list available through June
1, 2020: https://forms.gle/9QN7dxALJVAoRjMKA
This exception list is temporary. After June 1, 2020, you will be using the
multiple vantage point feature and may experience increased domain validation
failure rates unless you take action to ensure compatibility.
Our expert community, including Let’s Encrypt staff and many client developers,
monitor our community forum and are available to help if you get stuck.