Installed and activated php-fpm and mpm_event, but still starting prefork automatically

mod-php8.1 requires mpm-prefork because it's not thread safe. You have to DISABLE it, REMOVE the package and install the php-fpm package and configure/start php81-fpm.

php81-fpm is configured additionally from php.

After that, you need to install some server glue to make apache2 to talk to php81-fpm. This is typically located in /etc/apache2/conf-available and is typically called php-fpm.conf (or something close to that).

Here's the contents of mine:

# Comments: Redirect to local php-fpm.
#
# Depends: module/mod_proxy module/mod_proxy_fcgi
#
<IfModule proxy_fcgi_module>

    # Enable http authorization headers
    #
    <IfModule setenvif_module>
        SetEnvIfNoCase ^Authorization$ "(.+)" HTTP_AUTHORIZATION=$1
    </IfModule>

    <FilesMatch ".+\.ph(ar|p|tml)$">
        SetHandler "proxy:unix:/var/run/php-fpm.sock|fcgi://localhost"
    </FilesMatch>

    <FilesMatch ".+\.phps$">

        # Deny access to raw php sources by default
        # To re-enable it's recommended to enable access to the files
        # only in specific virtual host or directory
        #
        Require all denied

    </FilesMatch>

    # Deny access to files without filename (e.g. '.php')
    #
    <FilesMatch "^\.ph(ar|p|ps|tml)$">
        Require all denied
    </FilesMatch>

</IfModule>

Local variations will apply. See here (for Ubuntu…but should be pretty universal to most common Linuxen): https://unixcop.com/install-apache-and-php-ubuntu-22-04/

-- sw

It looks like you're trying to enable the php 8.1 module, which you don't need with php-fpm. I found this guide which gives some commands. Specifically, a command to specifically enable the configuration for php-fpm.

sudo a2enconf php8.1-fpm

Hopefully this guide will help you or give you some ideas.

Good luck.

Blake

The link referred to above only shows how to install plain old PHP, not FPM.

This is a pretty good guide… but there are many others:

https://www.cloudbooklet.com/how-to-install-php-fpm-with-apache-on-ubuntu-22-04/

Thank you all, guys!

@tech10,

Thanks! That guide really helped me!

@stevewi,

Great! Thank you.

So, I need to disable and remove the php8.1, right? Because I have not found a mod-php8.1. Is that right?

Regarding php-fpm, I have installed it and configured it (I think). Well, it seems it is working, I can see the status of it (through systemctl status php8.1-fpm), etc.

About the server glue you've mentioned, following that guide, I have done the following:

I have edited my /etc/apache2/sites-available/domain.conf and now it`s as follows:

<VirtualHost *:80>   
        ServerName www.domain.com
        ServerAlias www.domain.com

        Protocols h2 http/1.1

        ServerAdmin webmaster@localhost
        DocumentRoot /var/www/html/domain.com/public_html

         <Directory /var/www/html/domain.com/public_html>
         Options -Indexes +FollowSymLinks
         AllowOverride All
         Require all granted
         </Directory>       

        ErrorLog /var/www/html/domain.com/logs/error.log
        CustomLog /var/www/html/domain.com/logs/access.log combined

<Location /server-status>
     SetHandler server-status
     Order Deny,Allow
     Deny from all
  Allow from localhost
</Location>
RewriteEngine on
RewriteCond %{SERVER_NAME} =www.domain.com
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
  <Directory /var/www/html/domain.com/public_html/>
        Require all granted
        AllowOverride All
    </Directory>
</VirtualHost>

Do you know if the above configuration is OK?

@acanton77,

Thank you!

P.S.: now I have mpm_event running instead mpm_prefork. But I had to comment the below lines in my /etc/apache2/apache2.conf file, due to errors regarding these "directives" when trying to start Apache:

<IfModule mpm_event_module>
       StartServers              4
       MaxSpareServers          25
       MaxRequestWorkers        50
       MaxConnectionsPerChild 2000
</IfModule>

Do the above lines really need to be removed from here?

So, I need to disable and remove the php8.1, right? Because I have not found a mod-php8.1. Is that right?

I think it's called libapache-php something or other…

P.S.: now I have mpm_event running instead mpm_prefork. But I had to comment the below lines in my /etc/apache2/apache2.conf file, due to errors regarding these "directives" when trying to start Apache:

<IfModule mpm_event_module>
       StartServers              4
       MaxSpareServers          25
       MaxRequestWorkers        50
       MaxConnectionsPerChild 2000
</IfModule>

Do the above lines really need to be removed from here?

These are incorrect. mpm_event uses threads instead of "servers" (mpm_prefork uses processes…hence the "server" nomenclature…a server in apache2 is a process). You want it to look something like this:

# event MPM
# StartServers: initial number of server processes to start
# MinSpareThreads: minimum number of worker threads which are kept spare
# MaxSpareThreads: maximum number of worker threads which are kept spare
# ThreadsPerChild: constant number of worker threads in each server process
# MaxRequestWorkers: maximum number of worker threads
# MaxConnectionsPerChild: maximum number of requests a server process serves

<IfModule mpm_event_module>
  ThreadLimit             512 
  ServerLimit              32
  StartServers             25 
  MaxRequestWorkers       256
  MinSpareThreads          32
  MaxSpareThreads          64
  ThreadsPerChild         128
  MaxConnectionsPerChild   64
  MaxRequestsPerChild      64
</IfModule>

Adjust the numbers to suit your situation…although, these would be pretty suitable for a fairly small number of user requests per hour.

-- sw

Thank you very much. I think I've found the necessary package to remove, and have already removed it (libapache2-mod-php).

Now I checked the status of php8.1-fpm and it returns the following:

 Loaded: loaded (/lib/systemd/system/php8.1-fpm.service; enabled; vendor preset: enabled)
     Active: active (running) since Tue 2023-02-14 18:06:56 -03; 20h ago
       Docs: man:php-fpm8.1(8)
   Main PID: 49343 (php-fpm8.1)
     Status: "Processes active: 0, idle: 3, Requests: 2368, slow: 0, Traffic: 0req/sec"
      Tasks: 4 (limit: 1029)
     Memory: 194.0M
        CPU: 2min 52.469s
     CGroup: /system.slice/php8.1-fpm.service
             ├─49343 "php-fpm: master process (/etc/php/8.1/fpm/php-fpm.conf)" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" ""
             ├─49538 "php-fpm: pool www" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" ""
             ├─53146 "php-fpm: pool www" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" ""
             └─54754 "php-fpm: pool www" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" "" ""

I think everything is fine now, right.

And I finally edited my /etc/apache2/apache2.conf and added the lines you suggested. Everything seems to be working fine now.

But I'll research more about every one of that directives. :)

Also, do you know if the presence of the following line on /etc/apache2/sites-available/domain.conf is correct?

Protocols h2 http/1.1

Is that I really don't understood that in the guide I've followed, despite everything being running well now.

Thanks again, and please sorry for so many questions.

I think everything is fine now, right.

Looks like it… all the pairs of   ""   is just systemd being stupid (it's natural state IMHO)…

Also, do you know if the presence of the following line on /etc/apache2/sites-available/domain.conf is correct?

Protocols h2 http/1.1

The definitive documentation on Apache 2.4 can be found here: https://httpd.apache.org/docs/2.4/

The definitive documentation on Apache 2.4 directives can be found here: https://httpd.apache.org/docs/2.4/mod/directives.html

If you click on Protocols, you will find:

For example, if you want to support HTTP/2 for a server with TLS, specify:

Protocols h2 http/1.1

Valid protocols are http/1.1 for http and https connections, h2 on https connections and h2c for http connections. Modules may enable more protocols.

This is the answer you are seeking. Note h2/h2c are up and coming. Neither are standardized yet.

-- sw

Understood. Thank you very much for your help. I'll also take a look on that Apache documentation.