Good morning,
Unless domain1 and domain2 are owned by the same customer, you cannot access files from each to others. This is due to the open_basedir restrictions.
The solution is to install the shared library somewhere else, such as in the /usr/local/lib/php directory (you need to create that directory), and through relevant i-MSCP listener file, change the open_basedir parameter for all domains to add that directory. For best use, you should also add that path to the include_path (always through the listener file).
Assuming that you're using latest i-MSCP version, you can use the following i-MSCP listener file: https://github.com/i-MSCP/imsc…p_confoptions_override.pl
Basically put, the %configOptions hash from the i-MSCP listener file should looks as follows:
The listener file need to be copied in the /etc/imscp/listeners.d directory. Once you have edited the configuration part of the listener file, you need trigger a i-MSCP reconfiguration, else, the changes won't be taken into effect: perl /var/www/imscp/engine/setup/imscp-reconfigure -danv.
BTW: Don't forget that the listener file requires either FPM (recommended) or Fcgid.
Thread closed.