Bookstack

502 on OIDC logout

Edit /config/nginx/site-confs/default.conf inside the container. On the host, it’s under whatever directory you mapped to /config, so something like ./bookstack/config/nginx/site-confs/default.conf.

Open it and find the PHP block, which in the linuxserver image looks like this:

location ~ \.php$ {
    fastcgi_split_path_info ^(.+\.php)(/.+)$;
    fastcgi_pass 127.0.0.1:9000;
    fastcgi_index index.php;
    include /etc/nginx/fastcgi_params;
}

Add the buffer directives inside it:

location ~ \.php$ {
    fastcgi_split_path_info ^(.+\.php)(/.+)$;
    fastcgi_pass 127.0.0.1:9000;
    fastcgi_index index.php;
    include /etc/nginx/fastcgi_params;

    fastcgi_buffer_size 32k;
    fastcgi_buffers 16 16k;
    fastcgi_busy_buffers_size 32k;
}

Then test and reload without restarting the container:

docker exec bookstack nginx -t && docker exec bookstack nginx -s reload

(Replace bookstack with your container name.)

The linuxserver image only creates default.conf on first run and won’t overwrite it on updates, so your edit will persist. If a future image update introduces a new default, it saves it as default.conf.sample next to yours rather than replacing it.

If the error persists after this, check your .env (in /config/www/.env) for SESSION_DRIVER. If it’s set to cookie, switching it to file or database is the other big lever for shrinking headers.