Server

For the --server parameter, you can specify an ACME server directory URL, and you can also give a short friendly name for known CAs.

The supported short names are:

Short Name	ACME server URL
letsencrypt	https://acme-v02.api.letsencrypt.org/directory
letsencrypt_test	https://acme-staging-v02.api.letsencrypt.org/directory
buypass	https://api.buypass.com/acme/directory
buypass_test	https://api.test4.buypass.no/acme/directory
zerossl	https://acme.zerossl.com/v2/DV90

The short name will be treated as the same as the URL:

The following usages have the same meaning:

acme.sh --issue ....   --server  zerossl

-or-

acme.sh --issue ....   --server  https://acme.zerossl.com/v2/DV90