/server/cron.sh executes under /bin/sh and fails over "[[" tests

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.

 

Have you done that? The error message you show makes me suspect shell is dash, not bash.
What shows

Code:

ls -lh /bin/sh /usr/bin/sh

 

It is dash indeed:

Code:

# ls -lh /bin/sh /usr/bin/sh
lrwxrwxrwx 1 root root 4 Jun 29 12:31 /bin/sh -> dash
lrwxrwxrwx 1 root root 4 Jun 29 12:31 /usr/bin/sh -> dash

But why would /bin/sh be used in the first place? The shell for root user is not /bin/sh, it's /bin/bash

 

Thanks!
It (`dpkg-reconfigure dash`) fixed it: no more errors in `/var/log/ispconfig/cron.log` file and the acme.sh client works.
I'll have to double check my notes because I was pretty sure I had applied that part (and installation seemed to have been a complete success).

I'll also have to, for my own culture, understand what are the implication of `dpkg-reconfigure dash` and how this changes the root shell for cronjobs.