WP database connection error

[VPS running Debian 10; LEMP stack; ISPConfig 3.2.7p1]

After fixing issues installing ISPConfig3 from Autoinstaller script (wrong php version) I am unable to get a fresh WP install to connect to MariaDB

So far this is the only nginx vhost and I triple checked and reset mysql database (empty) and user. phpmyadmin can connect - I also tried adding port to hostname in wp-config.php, to no avail.

PHP versions 7.3, 7.4, 8.0, 8.1 are installed, I added them to ISPConfig as per tutorial, except default 7.3 which was showing since install.
Only php-fpm and HHVM (no fastCGI) are available from pull down menu, although I am guessing this is expected/unrelated.
Client does have suexec forced enabled.

Testing connection with a php script returns

Code:

Connection failed: SQLSTATE[HY000] [2002] No such file or directory 

nginx error.log has some errors I think are the issue

Code:

2022/02/26 16:13:45 [error] 1067#1067: *1 FastCGI sent in stderr: "PHP message: PHP Warning:  mysqli_real_connect(): (HY000/2002): No such file or directory in /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php on line 91PHP message: PHP Fatal error:  Uncaught Error: Call to a member function queryOneRecord() on bool in /usr/local/ispconfig/interface/lib/app.inc.php:169
Stack trace:
#0 /usr/local/ispconfig/interface/lib/app.inc.php(93): app->conf('interface', 'session_timeout')
#1 /usr/local/ispconfig/interface/lib/app.inc.php(401): app->initialize_session()
#2 /usr/local/ispconfig/interface/web/datalogstatus.php(34): require_once('/usr/local/ispc...')
#3 {main}
  thrown in /usr/local/ispconfig/interface/lib/app.inc.php on l

and later:

Code:

2022/02/26 19:21:11 [error] 16289#16289: *1 FastCGI sent in stderr: "PHP message: PHP Warning:  mysqli_query(): (HY000/1): Can't create/write to file '/tmp/#sql_869_0.MAI' (Errcode: 2 "No such file or directory") in /usr/local/ispconfig/interface/lib/classes/db_mysql.inc.php on line 300" while reading response header from upstream, client: 178.191.160.140, server: _, request: "GET /sites/web_vhost_domain_edit.php?id=1&type=domain HTTP/2.0", upstream: "fastcgi://unix:/var/lib/php7.3-fpm/ispconfig.sock:", host: "1xx.xx.xxx.xx:8080", referrer: "https://1xx.xx.xxx.xx:8080/index.php"

There are also a few (unrelated?) ssl errors in webserver log

Code:

SSL_do_handshake() failed (SSL: error:141CF06C:SSL routines:tls_parse_ctos_key_share:bad key share

It seems to me I need to include some path somewhere but I can not figure this out.

I am heading to bed now, but any help would be greatly appreciated, although I understand that this is (my) WP issue and not an ISPConfig bug

 

thank you very much

should have checked that myself but wood > trees

 

for the sake of completeness

I did run in further issues getting the wp install to work. the installer did run but failed to populate anything but the _options table. (unable to write error) even with chroot php-fpm disabled.

the decision to remove the db and db_user manually meant I ran into the "ISPConfig3 does no longer process job queue" problem. restarting the server mitigated this and created the new db

I ended up re-running the wp install script with

PHP:

define( 'DB_HOST', $_ENV{DATABASE_SERVER});

in wp-config.php instead of either localhost or 127.0.0.1 and the install went through.

Weirdly (and I seem to remember this problem from an install a few years back) after the install the fresh, newly chosen credentials did NOT work. I had to reset password via email.

 

That in wp-config.php actually will detect the database server value automatically but in my mind providing the one suggested by @till should work too, though I haven't tried it of course.