PHP-FPM: No protocol handler was valid for the URL /index.php, error 500

(Hope I'm doing the right thing, posting it as an issue and not in the forum, I'm not used to this)

Bug report:

On a production debian Wheezy server, LAMP, mysql 5.5.57-0+deb7u1-log, PHP 5.4.45, virtualmin stable and all, everything works fine with mod_fcgid as php execution mode. But if I switch to FPM, in Virtualmin's "Website Options" panel, the next time I reload the website for which I made the change, I have a blank error 500 in my web browser, and in Apache's error log:

[Tue Sep 19 22:01:34 2017] [warn] proxy: No protocol handler was valid for the URL /index.php. If you are using a DSO version of mod_proxy, make sure the proxy submodules are included in the configuration using LoadModule.

Having read , I made sure that, Webmin -> Servers -> Apache Webserver -> Global Configuration -> Configure Apache Modules , both proxy and proxy_http are checked: they were already checked.

I went as far as restarting the server, same issue. Switching back to mod_fcgid resolves the issue.

I thought PHP-FMP had left beta status, it's why I am reporting it in the Issues section. I don't ask for support (not like I need PHP-FPM at all costs). Instead, I was hoping a bug report would help. Once again, I hope it's not a bother. If it is indeed an unplanned bug, if you ever want more info, sure, otherwise, no worries.



You may be missing a needed Apache module. If you go to System Settings -> Re-Check Configuration, does it report that any dependencies needed for FPM mode are missing?

I just checked what you mentioned Jamie, and unless jailkit is a necessity, everything's fine, it seems.

Your system has 31.34 GB of memory, which is at or above the Virtualmin recommended minimum of 256 MB.
BIND DNS server is installed, and the system is configured to use it.
Mail server Postfix is installed and configured.
Postfix is configured to support per-domain outgoing IP addresses.
Apache is installed.
The following PHP versions are available : 5.4.45 (/usr/bin/php5-cgi), 5.4 (mod_php)
PHP-FPM support is available on this system.
Webalizer is installed.
Apache is configured to host SSL websites.
MySQL is installed and running.
ProFTPD is installed.
Logrotate is installed.
SpamAssassin and Procmail are installed and configured for use.
ClamAV is installed and assumed to be running.
Plugin AWstats reporting is installed OK.
Plugin DAV Login is installed OK.
Plugin Mailman is installed OK.
Plugin Protected web directories is installed OK.
Using network interface eth0 for virtual IPs.
IPv6 addresses are available, using interface eth0.
Default IPv4 address for virtual servers is (redacted)
Default IPv6 address for virtual servers is (redacted)
Default IP address is set to (redacted), which matches the detected external address.
Both user and group quotas are enabled for home and email directories.
All commands needed to create and restore backups are installed.
The selected package management and update systems are installed OK.
Chroot jails are not available : The Jailkit command jk_init was not found on your system - maybe the jailkit package is not installed?
.. your system is ready for use by Virtualmin.

Jailkit is an optional feature - you don't strictly need it.

Indeed, not needed, that's what Google told, so to say. Which leaves the issue intact.

I don't ask for assistance at all costs, but maybe - just maybe - you virtualmin guys could check on your end if noone else has the issue. The best I hope for you is that noone is facing it like that and it's a random anomaly :)

To my knowledge, we haven't had other users post a similar issue, but it also never hurts to get to the bottom of a potential bug :-)

What happens if you run the following, which will enable some Apache modules:

sudo a2enmod ssl
sudo a2enmod proxy
sudo a2enmod proxy_balancer
sudo a2enmod proxy_http

After that, restart Apache with "service apache2 restart".

Once you do that, are you able to access your site using PHP-FPM?