acme.sh VS acme-dns

Next, we will install acme.sh, a command-line tool for managing SSL/TLS certificates. I prefer acme.sh over certbot, as it does not depend on the OS version. For more details about acme.sh, check its GitHub repo here.

A very relevant question. Acme.sh, a similar shell script ACME client, had a remote code execution problem last year.

https://github.com/acmesh-official/acme.sh/issues/4668

As a result, any certificates issued (or renewed) after Feb 8th will not work on older Android devices (< 7.1.1), unless the ACME client has been configure to request an alternate certificate chain. The "alternate chain" workaround will also stop working on June 6th.

I need to support these older Android devices so I am looking for alternatives. I have seen ZeroSSL mentioned a few times; it is also the default CA for acme.sh (the ACME client I am using nowadays) [2]. They have a number of paid plans but ACME certificates are free [3].

I'll be testing this over the next few days, but I would also like to ask if people here have experience with ZeroSSL (good or bad :-). Any feedback would be helpful.

[1]: https://letsencrypt.org/2023/07/10/cross-sign-expiration.html

[2]: https://github.com/acmesh-official/acme.sh

[3]: https://zerossl.com/documentation/acme/

Huh, the environment variable thing was specifically aimed at acme.sh which rather arbitrarily changed the config value from ACMEDNS_UPDATE_URL to ACMEDNS_BASE_URL, never acknowledged this in a changelog and then silently failed after an automatic upgrade as recommended by the default install:

https://github.com/acmesh-official/acme.sh/commit/2ce145f359...

It's also cleared out my .account.conf files when run on the suggested cron.

I've started using updown which also monitors my TLS certs simply because I no longer trust the process to work as documented.

It depends on your provider though. I can tell from experience that with OVH and their API, it's been easy to set up the automatic renewal via DNS verification. Apparently, the official client has support for the DNS API of 159 providers: https://github.com/acmesh-official/acme.sh/wiki/dnsapi

For the few people here that happen to run a self-hosted email server with acme.sh for TLS key/cert generation and Cloudflare for DNS management, I have made a tool that i personally use to get a perfect 100% score on Internet.nl's email test.

All of this is to say it's a decent amount of work to save the hassle of deploying certbot or acme.sh on the remote machines, pick your poison.

Here is a really solid guide for setting up the ACME DNS challenge with pretty much any DNS provider

People wonder why I like using the shell-based ACME client like dehydrated (or acme.sh):

* https://packages.debian.org/search?keywords=dehydrated

* https://github.com/acmesh-official/acme.sh

Versus the official client certbot:

* https://packages.debian.org/search?keywords=python3-certbot

A kludgy as very long shell scripts are (thought to be), I have a better chance of being able to go through all the code and understand it than a dozen(+) Python libraries.

So today I figured out how to install acme.sh to my hosted server space for my websites, and used acme to issue an SSL certificate and install it for a domain. It uses LetsEncrypt, and ZeroSSL for the default Certificate Authority (CA). Then I notice that ZeroSSL only allows a free 90 day certificate, and only 3 of those before you have to pay. Is there any way to generate actual free SSL certificates that do not expire for a year or more and that can be renewed free? I have heard that most hosting plans now provide free SSL certs, so is my hosting company just providing cheap hosting but making money on the backend by charging for SSL certs?

Getting a wildcard certificate from LE might be a better option, depending on how easy the extra bit of if plumbing is with your lab setup.

You need to use DNS based domain identification, and once you have a cert distribute it to all your services. The former can be automated using various common tools (look at https://github.com/joohoi/acme-dns, self-hosted unless you are only securing toys you don't really care about, if you self host DNS or your registrar doesn't have useful API access) or you can leave that as an every ~ten weeks manual job, the latter involves scripts to update you various services when a new certificate is available (either pushing from where you receive the certificate or picking up from elsewhere). I have a little VM that holds the couple of wildcard certificates (renewing them via DNS01 and acmedns on a separate machine so this one is impossible to see from the outside world), it pushes the new key and certificate out to other hosts (simple SSH to copy over then restart nginx/Apache/other).

Of course you may decide that the shin if your own CA is easier than setting all this up, as you can sign long lived certificates for yourself. I prefer this because I don't need to switch to something else if I decide to give friends/others access to something.

As someone else said, it’s a huge pain to run your own dns services. However, if you want some separation, I recently saw https://github.com/joohoi/acme-dns

v0.9.1 is out and natively supports both https://github.com/joohoi/acme-dns and any dns provider available in https://github.com/acmesh-official/acme.sh

I have set up an acme-dns server to answer ACME DNS Challenges: https://github.com/joohoi/acme-dns

The DNS challenge can be easily automated using https://github.com/joohoi/acme-dns - you do need an IP you can run a DNS server on though.

If your server is not accessible over the internet, you can still use Let's Encrypt or ZeroSSL to get a certificate. You'll just need to set up a DNS Challenge for things to work. This is a little more complicated, but can work even if your DNS provider doesn't have an API. For example, I use Google Domains and Google DNS (not cloud DNS) for my DNS server, but I've got an instance of acme-dns running on VPS box that handles the DNS auth for me. It's how every machine on my local network has valid certificates - but I annoyingly need to renew them every 90 days.

It's a bit more involved, but you can set up wildcard certificates to update automatically. Certbot has some pre-made plugins for this for several DNS providers. If yours is not on that list, there's a tool called acme-dns which is a minimal DNS server you can run on your server and delegate _acme-challenge.yourdomain.com to. If you don't want to run that on your own, you can also use the publicly hosted server/API for it.

In case you're not already familiar with it: one thing I'd recommend is using https://github.com/joohoi/acme-dns to obtain the certificates. You basically just point the subdomain you need wildcard certs for at that DNS server (a one time thing, ie you don't have to do this every three months), and the related tool https://github.com/acme-dns/acme-dns-client can get the certificates in a nice, automated, way without you ever having to expose the private reverse proxy to the Internet.