Assume you have a ghost server ran at a host machine.
Oneday the host machine maybe out of space or you find a new cheap host,
or you have a new host that have power memory and performance.
Then you may need to transfer your ghost server to another new host.

tar your ghost server to a *.tar.gz

//blog is my ghost server root directory

$cd www/blog
$tar -zcvf blog.tar.gz blog

copy the blog.tar.gz to the new host

preinstall on new host

nginx
sudo apt-get install nginx

node.js
https://nodejs.org/en/download/
extract and add node bin path to env

ghost

npm i -g ghost-cli

acme.sh
https://github.com/Neilpang/acme.sh

configure on new host

tar cvf blog.tar.gz

nginx conf

sudo ln -sf blog/system/files/blog.conf /etc/nginx/sites-available/blog.conf
sudo ln -sf /etc/nginx/sites-available/blog.conf /etc/nginx/sites-enabled/blog.conf

start http server

ghost start

if you encounter systemd error, just follow the hint command(ghost linuxuser systemd) by ghost
and run ghost start again.

Before you start your ghost server, you should change the DNS record for your server. Since you changed host, the IP would changed.

enable https server via letsencrypt

sudo ln -sf blog/system/files/blog-ssl.conf /etc/nginx/sites-available/blog-ssl.conf
sudo ln -sf /etc/nginx/sites-available/blog-ssl.conf /etc/nginx/sites-enabled/blog-ssl.conf
acme.sh --issue --home /etc/letsencrypt --domain errong.win --webroot /home/errong_leng/www/blog/system/nginx-root --reloadcmd "nginx -s reload" --accountemail errong.leng@gmail.com

http nginx conf

server {
    listen 80;
    listen [::]:80;

    server_name errong.win;
    root /home/errong_leng/www/blog/system/nginx-root;

    location / {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $http_host;
        proxy_pass http://127.0.0.1:6666;
        
    }

    location ~ /.well-known {
        allow all;
    }

    client_max_body_size 50m;
}

https nginx conf

server {
    listen 443 ssl http2;
    listen [::]:443 ssl http2;

    server_name errong.win;
    root /home/errong_leng/www/blog/system/nginx-root;

    ssl_certificate /etc/letsencrypt/errong.win/fullchain.cer;
    ssl_certificate_key /etc/letsencrypt/errong.win/errong.win.key;

    location / {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $http_host;
        proxy_pass http://127.0.0.1:6666;
        
    }

    location ~ /.well-known {
        allow all;
    }

    client_max_body_size 50m;
}