Symptoms
-
PHP Composer page fails to load for a domain in Plesk. Either a blank page or one of the following error messages is shown in a web-browser:
500 error
Server Error
500 Error
Class "Zend_Db_Adapter_Exception" not found
Type Error
Message Class "Zend_Db_Adapter_Exception" not found
File Abstract.php
Line 144
ERROR: Uncaught Error: Class "Zend_Log_Exception" not found in /opt/psa/admin/plib/vendor/plesk/zf1/library/Zend/Log/Writer/Stream.php:81 ...
-
The following error message appears in
/var/log/plesk/panel.log
with debug mode enabled:ERR [panel] Exception: PHP Warning: file_get_contents(/etc/plesk-release): Failed to open stream: Too many open files; File: ...
Cause
sw-engine
Plesk service reaches the open files limit and can't load PHP Composer.
Resolution
Increase the open files limit for sw-engine:
-
Connect to the Plesk server via SSH.
-
Copy
sw-engine.service
unit file to/etc/systemd/system
:# cp /usr/lib/systemd/system/sw-engine.service /etc/systemd/system/
-
Open the copied file in a text editor. In this example, we are using the vi editor:
# vi /etc/systemd/system/sw-engine.service
-
Add the line below under the
[Service]
section:LimitNOFILE=180000
-
Save the changes and close the file.
-
Restart
daemon
andsw-engine
services:# systemctl daemon-reload && systemctl restart sw-engine.service