Preferred Chain - acmesh-official/acme.sh GitHub Wiki

Using --preferred-chain to select the alternate chain.

If the ACME CA provides multiple cert chains, you can use --preferred-chain to select one. Otherwise, it will get the default chain.

  1. For letsencrypt.org Staging Server:

https://letsencrypt.org/docs/staging-environment/

There are 2 chains provided:

Name Default
(STAGING) Pretend Pear X1 No
(STAGING) Bogus Broccoli X2 Yes

You select the chain like:

acme.sh  --issue -d example.com .....  --test    --preferred-chain  "(STAGING) Pretend Pear X1"

You can also use part of the name:

acme.sh  --issue -d example.com .....  --test    --preferred-chain  "X1"

It's also case-insensitive:

acme.sh  --issue -d example.com .....  --test    --preferred-chain  "x1"
  1. For Letsencrypt.org Production server:

    There are 2 chains provided:

    Name Default
    DST Root CA X3 Yes
    ISRG Root X1 No

    You select the chain like:

acme.sh  --issue -d example.com .....  --server letsencrypt   --preferred-chain  "ISRG Root X1"

You can also use part of the name:

acme.sh  --issue -d example.com .....  --server letsencrypt   --preferred-chain  "ISRG"

It's also case-insensitive:

acme.sh  --issue -d example.com .....  --server letsencrypt    --preferred-chain  "isrg"
  1. You can also set the default preferred chain for a specified CA(from v3.0.1).
acme.sh --set-default-chain  --preferred-chain "ISRG"   --server  letsencrypt

When you request a cert from letsencrypt in future, it will use the default preferred chain.