Hello, When debugging an issue with the acme.sh client (`acme.sh --issue` is called but `acme.sh --install-cert` is not) I finally noticed errors in the `/var/log/ispconfig/cron.log` file : Code: Sat 17 Jul 2021 11:08:10 PM UTC sh: 1: [[: not found Sat 17 Jul 2021 11:08:10 PM UTC sh: 1: 0: not found Sat 17 Jul 2021 11:08:10 PM UTC sh: 1: [[: not found They occurs when I enable SSL with Let's Encrypt for a website, the shell command created by PHP method `letsencrypt::get_acme_command()` is: Code: R=0 ; C=0 ; /root/.acme.sh/acme.sh --issue -d example.com -d www.example.com -w /usr/local/ispconfig/interface/acme --always-force-new-domain-key --keylength 4096; R=$? ; if [[ $R -eq 0 || $R -eq 2 ]] ; then /root/.acme. sh/acme.sh --install-cert -d example.com -d www.example.com --key-file '/var/www/clients/client1/web3/ssl/example.com-le.key' --fullchain-file '/var/www/clients/client1/web3/ssl/example.com-le.crt' --reloadcmd 'systemctl force- reload nginx.service' --log '/var/log/ispconfig/acme.log'; C=$? ; fi ; if [[ $C -eq 0 ]] ; then exit $R ; else exit $C ; fi As this command uses "[[" / double brackets to check for `acme.sh --issue` exit code (`R` variable) I can understand the failure if ran with /bin/sh. By altering this command to output some debug info, I was able to confirm it gets executed by root user using /bin/sh shell. What I don't understand is why it runs as /bin/sh although root's shell is /bin/bash (confirmed by a `echo $SHELL` or `getent passwd root` from a classic root SSH shell)... Have I failed to set an ISPConfig setting right? I did not found anything about root's shell (except the part of the installer that actively set it to /bin/bash) in the documentation. (I am using ISPConfig v3.2.5 on Debian v10) Thanks for you help.