Seafile Pro 7.1.10 with Plesk gives 502 Bad Gateway error

Hi,

following setup:

Strato VM with Ubuntu 18.04.5 LTS using Plesk 18.0.32 and subdomain with LetsEncrypt for cloud
Seafile Pro 7.1.10
Nginx 1.18.0.2
MariaDB 10.5.8

When accessing via https I get an 502 Bad gateway error. This setup has never worked.

Here is the nginx.conf for this subdomain

#ATTENTION!
#
#DO NOT MODIFY THIS FILE BECAUSE IT WAS GENERATED AUTOMATICALLY,
#SO ALL YOUR CHANGES WILL BE LOST THE NEXT TIME THE FILE IS GENERATED.

server {
	listen 85.214.191.79:443 ssl;

	server_name cloud.val-trackdays.de;
	server_name www.cloud.val-trackdays.de;
	server_name ipv4.cloud.val-trackdays.de;

	ssl_certificate             /opt/psa/var/certificates/scfIK2NBQ;
	ssl_certificate_key         /opt/psa/var/certificates/scfIK2NBQ;

	client_max_body_size 128m;

	root "/var/www/vhosts/val-trackdays.de/cloud.val-trackdays.de";
	access_log "/var/www/vhosts/system/cloud.val-trackdays.de/logs/proxy_access_ssl_log";
	error_log "/var/www/vhosts/system/cloud.val-trackdays.de/logs/proxy_error_log";

	#extension letsencrypt begin
	location ^~ /.well-known/acme-challenge/ {
		root /var/www/vhosts/default/htdocs;

		types { }
		default_type text/plain;

		satisfy any;
		auth_basic off;
		allow all;

		location ~ ^/\.well-known/acme-challenge.*/\. {
			deny all;
		}
	}
	#extension letsencrypt end

	location ~ /\.ht {
		deny all;
	}

	disable_symlinks if_not_owner "from=/var/www/vhosts/val-trackdays.de";

	add_header X-Powered-By PleskLin;

	include "/var/www/vhosts/system/cloud.val-trackdays.de/conf/vhost_nginx.conf";
}

server {
	listen 85.214.191.79:80;

	server_name cloud.val-trackdays.de;
	server_name www.cloud.val-trackdays.de;
	server_name ipv4.cloud.val-trackdays.de;

	client_max_body_size 128m;
}

and here the vhost_nginx.conf with the extra config via Plesk

proxy_set_header X-Forwarded-For $remote_addr;

location / {
proxy_pass http://127.0.0.1:8000;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Host $server_name;
proxy_read_timeout 1200s;

# used for view/edit office file via Office Online Server
client_max_body_size 0;

access_log      /var/log/nginx/seahub.access.log;
error_log       /var/log/nginx/seahub.error.log;

}
location /seafhttp {
rewrite ^/seafhttp(.*)$ $1 break;
proxy_pass http://127.0.0.1:8082;
client_max_body_size 0;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

proxy_connect_timeout  36000s;
proxy_read_timeout  36000s;
proxy_send_timeout  36000s;

send_timeout  36000s;

access_log      /var/log/nginx/seafhttp.access.log ;
error_log       /var/log/nginx/seafhttp.error.log;

}
location /media {
root /home/seafile/seafile-server-latest/seahub;
}

and here is the ccnet.conf file

[General]
SERVICE_URL = https://cloud.val-trackdays.de

[Database]
ENGINE = mysql
HOST = 127.0.0.1
PORT = 3306
USER = seafilesql
PASSWD = xxxxxxxxxxxxxx
DB = ccnet-db
CONNECTION_CHARSET = utf8

and here is the seafile.conf file

[fileserver]
port = 8082
host = 127.0.0.1

[database]
type = mysql
host = 127.0.0.1
port = 3306
user = seafilesql
password = xxxxxxxxxxx
db_name = seafile-db
connection_charset = utf8

and here is seahub_settings.py

- - coding: utf-8 - -

SECRET_KEY = “xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx’”
FILE_SERVER_ROOT = ‘https://cloud.val-trackdays.de/seafhttp’

DATABASES = {
‘default’: {
‘ENGINE’: ‘django.db.backends.mysql’,
‘NAME’: ‘seahub-db’,
‘USER’: ‘seafilesql’,
‘PASSWORD’: ‘xxxxxxxxxxxxx’,
‘HOST’: ‘127.0.0.1’,
‘PORT’: ‘3306’
}
}

Here is an error log from seahub.error.log

2021/01/21 17:02:11 [error] 377#0: *26 upstream prematurely closed connection while reading response header from upstream, client: 185.156.75.59, server: cloud.val-trackdays.de, request: “GET / HTTP/1.1”, upstream: “http://127.0.0.1:8000/”, host: “cloud.val-trackdays.de
2021/01/21 17:02:11 [error] 377#0: *26 upstream prematurely closed connection while reading response header from upstream, client: 185.156.75.59, server: cloud.val-trackdays.de, request: “GET /favicon.ico HTTP/1.1”, upstream: “http://127.0.0.1:8000/favicon.ico”, host: “cloud.val-trackdays.de”, referrer: “https://cloud.val-trackdays.de/

Anything else needed? Let me know…

thx,
Lino