2

I'm on a shared hosting without SSH access and I host there 20+ domains. The domains don't have a dedicated public IP address, so I'm using TLS/SNI with a shared SSL certificate for all the domains that I'm able to upload into the hosting administration.

Since I don't have SSH access to the server, I used the Let's Encrypt Manual method (http://letsencrypt.readthedocs.org/en/latest/using.html#manual) on a local computer to issue the certificate.

It took a lot of time to validate all the domains (www + non-www = 20 * 2 challenges) and now the SSL certificate is going to expire (the certificate is only for 90 days).

It is possible to renew the certificate without doing the challenges again? I have the private key for the certificate, so can't they validate the domains based on that?

2

As Steffen metioned it is not possible to do the renewals without domain re-validation.

BUT even without SSH access it is possible to automate the Let's Encrypt renewal request which shoould solve your manual validation problem. Have a look at: Lescript on GitHub

The challenges are completed by creating the files and folders using PHP. The only thing you need to do is run this script every 90 days. It generates the SSL certificate into your webroot and you upload it into your hosting administration.

The script requirements are:

  • PHP 5.3 and up
  • OpenSSL extension
  • Curl extension

Before running the script you should also disable all the .htaccess mod_rewrite rules that rewrite URL to it's canonical form. Otherwise when validating domain.com it may rewrite the validation URL to www.domain.com and the challenge will fail.

2

It is possible to renew the certificate without doing the challenges again? I have the private key for the certificate, so can't they validate the domains based on that?

With the private key you could only prove that you are in the possession of the private key. You could not prove that you own the domain too. But a certificate should be used to validate access to a specific host and not the access to a specific key. That's why you need to re-validate the domain.

Just imagine if you would buy a domain from somebody and this one could create a certificate for the domain for the next 50 years - just because he has once owned the domain even if it was sold long ago.

  • I understand your point, but: a) The certificate is only for 90 days, you buy the domain for at least 365 days. So you have to revalidate 4 times a year, which is a lot of wasted time using manual method. b) If they want to prove that you still own the domain, they can save the domain's whois record when you are doing the first validation, and then they can just do the comparation when you are revalidating with your private key. – Joudicek Jouda Feb 10 '16 at 8:59
  • @JoudicekJouda: whois records are not a source usable for such trust relationships. They are more like a phone book which might have wrong or out of date entries. If you want to make really sure that there is a specific person behind a phone number you don't look it up in the phone book and blindly believe the entries, but you call the number. – Steffen Ullrich Feb 10 '16 at 9:12

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.