1st case :

you've low on RAM we recommend adding at least 1.5-2 Gb of available ram to compile PHP 7.xx and 8.xx as the compiler needs more memory for this version of PHP

you can check if you've sufficient RAM by this command :

free -h

example output :

root@server:~# free -h
               total        used        free      shared  buff/cache   available
Mem:           1.9Gi       328Mi        90Mi        56Mi       1.4Gi       1.5Gi
Swap:          2.0Gi        38Mi       1.9Gi

here you can see Mem which indicates the total RAM and you need to check the `available` memory which should be more than 1.5Gb listed

Also for low memory servers, we always recommend adding at least 2Gb of Swap memory to prevent OOM (Out of memory) incidents.

2nd Case :

You're using an outdated OS that is already ON EOL period

Like Centos 6 and Centos 8 which are already in the EOL period and many repositories are disabled in this OS and you may experience non-availability of packages and dependencies which are required to build the PHP.

We always recommend upgrading you to Following OS :

Centos 7
Centos 8 stream
AlmaLinux 8
Rocky Linux 8
Oracle Linux 7 and 8

3rd Case :

Internet issue/Resolver issue

We've seen some cases where the OS resolver is not correctly set and many packages are not downloading due to the resolver failing.
Ensure you have the correct resolver added in /etc/resolv.conf

you can add this lines at the end of the file in /etc/resolv.conf :

nameserver 1.1.1.1
nameserver 8.8.8.8

* Your server provider might also have some custom resolvers

Now lock the file :

chattr +i /etc/resolv.conf

The next step is to reboot the server :

reboot

Make sure you check the logs as it can be also any other reason

Configuration locations MAIN PHP-CGI
/usr/local/php/php.d/snuffleupagus.ini

Configuration locations PHP-FPM
/opt/alt/php-fpm70/usr/php/php.d/snuffleupagus.ini
/opt/alt/php-fpm71/usr/php/php.d/snuffleupagus.ini
/opt/alt/php-fpm72/usr/php/php.d/snuffleupagus.ini
/opt/alt/php-fpm73/usr/php/php.d/snuffleupagus.ini
/opt/alt/php-fpm74/usr/php/php.d/snuffleupagus.ini
/opt/alt/php-fpm80/usr/php/php.d/snuffleupagus.ini
/opt/alt/php-fpm81/usr/php/php.d/snuffleupagus.ini

Configuration locations PHP-CGI
/opt/alt/php70/usr/php/php.d/snuffleupagus.ini
/opt/alt/php72/usr/php/php.d/snuffleupagus.ini
/opt/alt/php74/usr/php/php.d/snuffleupagus.ini
/opt/alt/php71/usr/php/php.d/snuffleupagus.ini
/opt/alt/php73/usr/php/php.d/snuffleupagus.ini
/opt/alt/php80/usr/php/php.d/snuffleupagus.ini
/opt/alt/php81/usr/php/php.d/snuffleupagus.ini

Configuration files are located in the folder
/usr/local/cwp/.conf/phpdefender

Predefined rules are in the folder
/usr/local/cwp/.conf/phpdefender/rules/

More info about it

https://snuffleupagus.readthedocs.io/

Module file location (depends on the PHP version)
PHP-FPM: /opt/alt/php-fpm72/usr/lib/php/extensions/no-debug-non-zts-20151012/snuffleupagus.so
PHP-CGI: /opt/alt/php72/usr/lib/php/extensions/no-debug-non-zts-20151012/snuffleupagus.so

Copy the default templates and save/create it as timeout tpl and stpl:

cd /usr/local/cwpsrv/htdocs/resources/conf/web_servers/vhosts/httpd/php-fpm/
cp default.stpl timeout.stpl
cp default.tpl timeout.tpl

Now you need to edit the both templates "timeout.tpl" and "timeout.stpl" and add this line:

ProxyTimeout 90

under

<IfModule proxy_fcgi_module>

and save it.

** ProxyTimeout 90 is the limit that allows the script to run for 90 seconds before it gets hit with the timeout threshold.
Increase it according to your needs, please don't use too high numbers to avoid server overloads.

eg :

<IfModule proxy_fcgi_module>
    ProxyTimeout 90
    <FilesMatch \.php$>
        SetHandler "proxy:%backend_fcgi%|fcgi://localhost"
    </FilesMatch>
</IfModule>

Now all you need is to create a custom configuration under webserver domain config and select the template or choose this template as a default in the webserver main config.

More info about the custom templates can be found here.

How to Edit root side php configuration file :

Login to CWP admin and navigate to cwpAdmin >> Php settings find the module name >> PHP.ini Configuration here you can edit php options, this module is only for php switcher/main php

To edit php.ini for php-fpm selector navigate to cwpAdmin >> Php settings find the module name >> PHP-FPM Selector and in this module you will be showed multi php version and for each version there is an "[Edit php.ini]" option you can do necessary changes there. Don't forget to reload/restart the fpm service after php options are modified.

To edit php.ini for php-cgi selector navigate to cwpAdmin >> Php settings find the module name >> PHP Selector 2 and in this module you will be showed multi php version and for each version there is an "[Edit php.ini]" option you can do necessary changes there.

How to create User side php configuration file :

We have two options either the user needs to create the files manually (via file manager, FTP or sFTP) or edit the PHP options from the user panel option.

Login to user panel find Edit php.ini option :

Now choose the desired domain name for which you want to create php.ini or .user.ini for in the doc root path, also you can disable some option by clicking on "tick mark" to toggle disable and enable options:

Once you edited the config click on the update changes button to save it.

Also you can directly write your own PHP config in advanced php.ini editor :

when creating manual PHP configuration via FTP, sFTP or file manager always create two .ini files with the same contents i.e. php.ini and .user.ini so when you switch fpm and CGI PHP respectively, so you don't need to come back to create them again.

This tutorial will work with php 5.3.29 - php 5.6.40 only.
For php 7.x use sqlsrv which is already in php options.

To build MSSQL with php 5.6/5.x.x just follow this steps :

Run this commands one by one (this will install freetds and its header files) :

yum install -y freetds freetds-devel freetds-libs
ln -s /usr/lib64/libsybdb.so.5.1.0 /usr/lib/libsybdb.so
ln -s /usr/lib64/libsybdb.so.5.1.0 /usr/lib64/libsybdb.so

Now go to php selector/php-fpm selector and hit "Reset options" under php 5.6 (or 5.x.x) and add this to "Manual options" config then save it :

[mssql]
default=0
option="--with-mssql"
info-file=config-path.txt

Next step is to choose the mssql option with your desired php ext options from "Select Options" and hit save custom config go "Back" and click on "Start Compiler (build & install)" wait for the php build and check php info.

This tutorial will work with php 5.3.29 - php 5.6.40 only for php 7.x use sqlsrv which is already in php options.

To build MSSQL with php 5.6/5.x.x just follow this steps :

Run this commands one by one (this will install freetds and its header files) :

yum install -y freetds freetds-devel freetds-libs
ln -s /usr/lib64/libsybdb.so.5.1.0 /usr/lib/libsybdb.so
ln -s /usr/lib64/libsybdb.so.5.1.0 /usr/lib64/libsybdb.so

Now go to php selector/php-fpm selector and hit "Reset options" under php 5.6 (or 5.x.x) and add this to "Manual options" config then save it :

[mssql]
default=0
option="--with-mssql"
info-file=config-path.txt

Next step is to choose the mssql option with your desired php ext options from "Select Options" and hit save custom config go "Back" and click on "Start Compiler (build & install)" wait for the php build and check php info.

PHP switcher :

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /usr/local/php/php.d/disabled_function.ini

PHP-CGI selector :

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php53/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php54/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php55/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php56/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php70/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php71/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php72/usr/php/php.d/disabled_function.ini

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php73/usr/php/php.d/disabled_function.ini

PHP_FPM Selector :
** Don't forget to restart php-fpm after changes

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm53/usr/php/php.d/disabled_function.ini && service php-fpm53 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm54/usr/php/php.d/disabled_function.ini && service php-fpm54 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm55/usr/php/php.d/disabled_function.ini && service php-fpm55 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm56/usr/php/php.d/disabled_function.ini && service php-fpm56 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm70/usr/php/php.d/disabled_function.ini && service php-fpm70 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm71/usr/php/php.d/disabled_function.ini && service php-fpm71 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm72/usr/php/php.d/disabled_function.ini && service php-fpm72 restart

echo "disable_functions = exec, system, popen, proc_open, shell_exec, passthru, show_source" > /opt/alt/php-fpm73/usr/php/php.d/disabled_function.ini && service php-fpm73 restart

To enable it back, simply delete disabled_function.ini file for the PHP version you want and restart apache/php-fpm.

First update the server :

yum -y update

Switch into the /usr/local/src directory.

cd /usr/local/src

Install Composer by using cURL

curl -sS https://getcomposer.org/installer | php

To use Composer globally run this below command ensure to use as user and user should have full shell access in order to use it :

mv -f composer.phar /usr/local/bin/composer

to check composer version :

composer -V

to run composer via different php version use full path of php bin and composer path eg :

/usr/local/bin/php /usr/local/bin/composer command

All selectors php bin path can be found in /opt/alt

eg :

/opt/alt/php73/usr/bin/php /usr/local/bin/composer command

PHP-FPM Selector
in CWP.admin left menu go to WebServer Settings --> Select WebServers
at bottom uncheck "Force Apache to use PHP-FPM Selector"

If you have used per domain conf then you would also need to make changes there
in CWP.admin left menu go to WebServer Settings --> WebServers Domain Conf

select users who have active fpm and use button "Delete Configuration" or make changes to not use php-fpm by selecting php-cgi-

PHP(cgi) Selector
Edit all .htaccess files and remove the custom lines starting like
AddHandler application/x-httpd-phpXXX

Info:
http://wiki.centos-webpanel.com/php-selector

With cwp we give you these 3 main tools to run php in many different ways.

- PHP Switcher
- PHP Selector
- PHP-FPM Selector

PHP Switcher
This is the main PHP version in cwp which is used as a default for all new clients and domains.
You can have only a single version active at the same time but you can select which you want to use, versions: 5.3, 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3

More info: http://wiki.centos-webpanel.com/php-version-switcher

PHP Selector
This are additional PHP versions which users can run all at the same time even as a different per folder, so you can run all versions at the same time and unlimited as a different per folder, versions: 5.3, 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3

More info: http://wiki.centos-webpanel.com/php-selector

PHP-FPM Selector
This are PHP-FPM versions, you need to activate them via "WebServers Domain Conf" from the left menu in the cwp.admin.
You can run only a single PHP-FPM version per domain/subdomain but you can select any of the following versions: 5.3, 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3
Interesting here is that via "WebServers Domain Conf" you can run a different version for each domain/subdomain under the same account.

The best of all is that you combine almost all of them, here are the few examples:

EXAMPLE
- domain cwp.com running main php version via PHP Switcher which is set to 5.6.
- subfolder of domain cwp.com/admin/ is running PHP Selector with version 5.4
- subfolder of domain cwp.com/admin/demo/ is running PHP Selector with version 5.3
- subfolder of domain cwp.com/test/ is running PHP Selector with version 7.0
- subdomain forum.cwp.com is running PHP-FPM Selector with version 7.2 via "WebServers Domain Conf"
- subdomain demosite.cwp.com is running PHP-FPM Selector with version 7.1 via "WebServers Domain Conf"

* Important thing is that if you use "WebServers Domain Conf" to activate php-fpm for that domain then all subfolders will use that version, but you can add multiple domains or subdomains to the same folder/path location and then again use a different php/php-fpm version for each of them.

* Don't forget that via "WebServers Domain Conf" you can also use different WebServers setup, an example is to activate Nginx with php-fpm or to use nginx/apache with php-fpm...and many other options.

More detailed:
http://forum.centos-webpanel.com/high-performance/cwp-webservers-detailed-info/