Unable to Update PHP Version

[Nik482]

We just upgraded our myBB to 1.8.24, and asked our host to upgrade our SQL to MariaDB 10.233. Now we'd like to use a version of PHP that's still supported, but when I choose a different version, either our forum goes completely white or we get an error message, depending on which PHP version I choose:

502 Bad Gateway

nginx

If I choose the oldest PHP version, the forum works fine, but it's in the 5 series and seems like a security risk. I have contacted the host/server for help, and, though they readily upgraded our SQL, they say changing a PHP version is not something they handle, that we need a developer to determine whether our website is compatible. I am not sure where to go from here.

[Crazycat]

I think you have a trouble with your php-fpm configuration.
Do you use it via socks or via proxy pass ?

[Nik482]

I'm going to venture a guess -- under Apache & nginx Settings, "Proxy mode" is checked under nginx settings. Maybe this indicates proxy pass?

[selected] Proxy mode
Nginx proxies requests to Apache. Turn off to stop using Apache.

[selected] Smart static files processing
If turned off, Apache will process all requests for static files. nginx will only pass requests and responses without modification. Turn off this option only for troubleshooting.

[not selected] Serve static files directly by nginx
ac3 avi bmp bz2 css cue dat doc docx dts eot exe flv gif gz htm html ico img iso jpeg jpg js mkv mp3 mp4 mpeg mpg ogg pdf png ppt pptx qt rar rm svg swf tar tgz ttf txt wav woff woff2 xls xlsx zip

[not selected] Specify file extensions separated by spaces or by the "|" symbol. Requests for these files will be handled by nginx and never reach Apache. Caution: Apache rewrite rules will not be applied.

[not selected] Enable nginx caching
Caching may reduce website response time and server load, but should be used with care.

I found a php-info/id/1 file that includes this:

Configure Command

--enable-ftp' '--enable-SOCKETS' '--enable-sysvsem' '--enable-sysvshm' '--enable-sysvmsg' '--with-kerberos' '--enable-calendar' '--with-libxml-dir=/usr' '--enable-xml' '--with-system-tzdata' '--enable-pcntl' '--with-imap=shared' '--with-imap-ssl' '--enable-mbstring=shared' '--enable-mbregex' '--with-gd=shared' '--enable-bcmath=shared' '--enable-dba=shared' '--with-xmlrpc=shared' '--with-ldap=shared' '--with-ldap-sasl' '--with-mysql=shared,/usr' '--with-mysqli=shared,/usr/bin/mysql_config' '--with-mysql-SOCK=/var/lib/mysql/mysql.SOCK' '--enable-dom=shared'

Which may indicate socks.

---

This is probably it -- under Apache settings, these are all checked/selected, and I don't see any options with the word "sock" in the list at all:

proxy
proxy_connect
proxy_fdpass
proxy_scgi

proxy_ajp
proxy_express
proxy_ftp
proxy_wstunnel

proxy_balancer
proxy_fcgi
proxy_http