Ghost Blog Upgrade Guide

Ghost

When I first started building this site, the Ghost version I used was the Chinese edition of 0.7.4. That very early version also had quite a few hacky tricks you could play with. Recently, when some friends around me also started experimenting with Ghost, I discovered that many new features in the latest version are extremely appealing: for example, the latest version has long supported inserting tables in Markdown, and it also supports LaTeX. The lack of support for inserting tables in Markdown used to be quite painful. The previous workaround was to publish the article on GitHub, take a screenshot, and then upload the image to Ghost.

Since several years have passed, if I am going to upgrade, I might as well upgrade directly to the latest version. As of the time of this article, the current latest version is Ghost 1.24.8. Next, I will write up some upgrade guidance. If you are also using the Chinese edition of Ghost 0.7.4 like I was and want to upgrade to the latest version, you can take a look at my upgrade journey.

Preparation

The preparation work is, of course, backing up the old version’s configuration and data. Here is a checklist of what needs to be backed up:

  • Database file Export all post data through the Ghost admin system; this is essentially a JSON file exported from MySQL.
  • Theme files ghost/content/themes/
  • The server-side Ghost configuration file config.js
  • The ghost.conf configuration file under Nginx
  • The entire Ghost directory on the server Backing up the entire directory is optional. It is mainly to allow rollback if something goes wrong, and to recover data if anything is lost.

Starting the Upgrade

Ghost changed significantly after V1.XX, because many convenient scaffolding tools were introduced, such as Ghost, Ghost-CLI, and so on. Upgrading from 0.7.4 is considered a breaking change, so these Ghost tools all need to be installed from scratch.

Ghost is a fully open source, hackable platform for building and running a modern online publication.

Before installing the latest version of Ghost, please read the official documentation first:
getting-started-guide Install & Setup (production)

The rest of this article basically follows the steps in that English documentation, with some additional issues I ran into myself. The writing will keep the order of the problems encountered consistent with the installation sequence, and I hope it can provide readers with some help when upgrading.

Environment Configuration

1. Environment Dependencies

  • At least 1 GB of memory (or configure a swap partition)
  • Systemd (included with CentOS 7)
  • Node.js ( v8.9+, v6.9+, v4.5+ )
  • MySQL (or sqlite3)
  • nginx (if you need to configure SSL and use https, then nginx >= 1.9.5)
  • A non-root user with sudo privileges (the username also cannot be ghost). This is very important, and this special user will be emphasized below.

2. Configure a Swap Partition

The purpose of a swap partition is that when physical memory is insufficient, the system places data into swap, so swap acts as virtual memory. Ghost requires at least 1 GB of physical memory; otherwise, it will report an error. This can be resolved by configuring a swap partition (if you have 1 GB or more, you do not need to configure it).

Check the host’s physical memory and virtual memory:

$ free

total used free shared buff/cache available

Mem: 1016168 100360 293520 356 622288 746024

Swap: 0 0 0

Create 1024k empty files of 1k each in /var/swap:

$ dd if=/dev/zero of=/var/swap bs=1k count=1024k

1048576+0 records in
1048576+0 records out
1073741824 bytes (1.1 GB) copied, 18.4951 s, 58.1 MB/s

Create a swap partition:

$ mkswap /var/swap

Setting up swapspace version 1, size = 1048572 KiB
no label, UUID=9a1b4bf2-cc39-4ab7-8dd9-9e0f25d0695d

Enable the swap partition:

$ swapon /var/swap

swapon: /var/swap: insecure permissions 0644, 0600 suggested.

Write partition information:

$ echo '/var/swap swap swap default 0 0' >> /etc/fstab

Check the swap partition size again:

$ free

total used free shared buff/cache available
Mem: 1016168 100360 293520 356 622288 746024
Swap: 1048572 0 1048572

3. Check Node.js

Check the installed Node.js version:

$ node -v

v8.11.3

Note: The latest version of Ghost supports Node.js versions v8.9+, v6.9+, and v4.5+.

Check the node.js installation path:

$ sudo which node

/bin/node

Note: Node.js must be installed in a system path, such as /usr/bin/node or /usr/local/bin/node. Using nvm to manage Node.js is not recommended, because nvm installs Node.js under user paths such as /root or /home, and relying on symlinks will not work. If you must use nvm, you can use it to install Node.js in a system path (see Install system-wide Node.js with NVM: the painless way).

4. Check MySQL

Check the MySQL version:

$ mysqld -V

mysqld Ver 5.7.22 for Linux on x86_64 (MySQL Community Server (GPL))

Note: We recommend using MySQL 5.7.x. Do not use 8.x; otherwise, Ghost will fail to connect to MySQL.

Check whether the MySQL service is running:

$ systemctl is-active mysqld

active

Log in to MySQL as the MySQL root user:

$ mysql -u root -p -h localhost

Enter the MySQL root user password:

Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.22

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

Ensure that the root user can log in to MySQL normally.

Since we are upgrading Ghost, the MySQL configuration should already be in place. In this subsection, you only need to verify that the account is still usable.

5. Check nginx

Check the nginx version:

$ nginx -v

nginx version: nginx/1.15.0

Note: If you need to configure SSL to use HTTPS, the nginx version must be 1.9.5 or later.

Check whether the nginx service is running:

$ systemctl is-active nginx

active

Use the IP address to confirm that you can access the nginx welcome page, or the welcome page you modified yourself.

Start Installation

1. Install Ghost-CLI

Ghost-CLI makes it easy to manage the future state of Ghost and perform upgrades. After installing Ghost-CLI, future version upgrades only require running ghost update. So this breaking update should only be painful this once.

Install ghost-cli globally using npm:

$ sudo npm i -g ghost-cli

Check the installed ghost-cli version:

$ ghost -v

Ghost-CLI version: 1.8.1

2. Create a New User

Note: If you already have a non-root user with sudo privileges, skip this step.

Create a new user:

$ adduser <user>

Note: <user> is the username of the new user. Note that this name cannot be ghost, because Ghost creates a user named ghost.

Set the user password:

$ passwd <user>

Enter the user’s password twice.

Grant write permission to the /etc/sudoers file:

$ chmod -v u+w /etc/sudoers

Edit the file:

$ vim /etc/sudoers

Find:


## Allow root to run any commands anywhere
root    ALL=(ALL)       ALL

Add below:


# This user does not need to enter a password when using the sudo command
<user>    ALL=(ALL)       NOPASSWD:ALL

# or this user needs to enter a password when using the sudo command
<user>    ALL=(ALL)       ALL

Save and exit, then restore the permissions on /etc/sudoers:

$ chmod -v u-w /etc/sudoers

3. Configure Ghost

Create the directory. Switch to a non-root user with sudo privileges, and make sure the username is not ghost:

$ su - <user>

Note: ghost-cli creates a system user and group named ghost to run Ghost automatically.

Create the site directory and set permissions:

$ sudo mkdir -p /var/www/ghost
$ sudo chown <user>:<user> /var/www/ghost
$ sudo chmod 775 /var/www/ghost

Note: <user> is the username of the currently logged-in non-root user.

Go to the website directory:

$ cd /var/www/ghost

4. Install Ghost

Because we are upgrading directly in the production environment, we use the MySQL database. In a local environment, the sqlite3 database is used.

In the current directory, skip the system checks and install Ghost using MySQL as the database.

Although the official documentation lists Ubuntu 16.04 as the recommended OS, Ghost can be installed on CentOS as well; just add the --no-stack option.

$ ghost install --no-stack

✔ Checking system Node.js version
✔ Checking logged in user
✔ Checking current folder permissions
ℹ Checking operating system compatibility [skipped]
✔ Checking for a MySQL installation
✔ Checking memory availability
✔ Checking for latest Ghost version
✔ Setting up install directory
✔ Downloading and installing Ghost v1.24.8
✔ Finishing install process
? Enter your blog URL: (http://localhost:2368)

Enter the full access path to your website https://halfrost.com

Press Enter:

? Enter your blog URL: [https://halfrost.com](https://halfrost.com)
? Enter your MySQL hostname: (localhost)

Enter the MySQL login address. For a local login, use localhost and press Enter:

? Enter your MySQL hostname: localhost
? Enter your MySQL username:

Input root:

? Enter your MySQL username: root
? Enter your MySQL password: [input is hidden]

Enter the MySQL root user password:

? Enter your MySQL password: [hidden]
? Enter your Ghost database name:

Enter the name of the database to create; press Enter to use the default:

✔ Configuring Ghost
✔ Setting up instance
Running sudo command: chown -R ghost:ghost /var/www/ghost/content
✔ Setting up "ghost" system user
? Do you wish to set up "ghost" mysql user? (Y/n)

Press Enter to confirm automatically creating the MySQL user:

? Do you wish to set up "ghost" mysql user? Yes
✔ Setting up "ghost" mysql user
? Do you wish to set up Nginx? (Y/n)

Press Enter to confirm automatic nginx setup:

? Do you wish to set up Nginx? Yes
Nginx is not installed. Skipping Nginx setup.
ℹ Setting up Nginx [skipped]
Task ssl depends on the 'nginx' stage, which was skipped.
ℹ Setting up SSL [skipped]
? Do you wish to set up Systemd? (Y/n)

I found that Ghost-CLI still doesn’t recognize the installed nginx on CentOS, so I configured it manually afterward.

Simply pressing Enter does indeed automatically set up the system service:

? Do you wish to set up Systemd? Yes
✔ Creating systemd service file at /var/www/ghost/system/files/ghost_halfrost-com.service
Running sudo command: ln -sf /var/www/ghost/system/files/ghost_halfrost-com.service /lib/systemd/system/ghost_halfrost-com.service
Running sudo command: systemctl daemon-reload
✔ Setting up Systemd
Running sudo command: /var/www/ghost/current/node_modules/.bin/knex-migrator-migrate --init --mgpath /var/www/ghost/current
✔ Running database migrations
? Do you want to start Ghost? (Y/n)

At this point, it will not start successfully if you try to launch it, because the nginx configuration is from an older version, and the configuration fields have changed in the new version.

5. Configure nginx

Create a new configuration file:

$ sudo vim /etc/nginx/conf.d/ghost.conf

Write the configuration. The following is my configuration, provided only as an example:

server {  
    listen 443 default_server ssl http2;
    server_name halfrost.com www.halfrost.com;
    
    add_header Strict-Transport-Security "max-age=63072000; includeSubdomains; preload";
    add_header X-Frame-Options DENY;
    add_header X-Content-Type-Options nosniff;
    add_header X-Xss-Protection 1;

    ssl on;
    ssl_certificate /etc/letsencrypt/live/halfrost.com/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/halfrost.com/privkey.pem; # managed by Certbot
    ssl_prefer_server_ciphers on;
    ssl_protocols       TLSv1 TLSv1.1 TLSv1.2;
    ssl_ciphers "ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA:ECDHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA:ECDHE-RSA-DES-CBC3-SHA:EDH-RSA-DES-CBC3-SHA:AES256-GCM-SHA384:AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:AES256-SHA:AES128-SHA:DES-CBC3-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!DES:!MD5:!PSK:!RC4";

    location / {
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   Host      $http_host;
        proxy_pass         http://127.0.0.1:2368;
    }

}


server {  
        listen 80;
        server_name halfrost.com www.halfrost.com;
	rewrite ^(.*)  https://$server_name$1;

        #if ($http_user_agent !~* baidu.com){ 
        #        return 301 https://$host$request_uri;
	#}

	location /.well-known/acme-challenge/ {
            	alias /var/www/halfrost.com/.well-known/acme-challenge/;
            	try_files $uri =404;
        }

        location / {
                proxy_set_header   X-Real-IP $remote_addr;
                proxy_set_header   Host      $http_host;
                proxy_pass         http://127.0.0.1:2368;
                client_max_body_size 35m;
        }
}

Note: Change the server_name field to the domain name(s) you have configured DNS for. Separate multiple domain names with spaces.

Save and exit, then restart the nginx service:

$ sudo systemctl restart nginx

6. Other Ghost Configuration

Under the /var/www/ghost/ directory, there is a config.production.json file, which contains some configuration for Ghost. Here is my configuration as an example:

{
  "url": "http://halfrost.com",
  "server": {
    "port": 2368,
    "host": "127.0.0.1"
  },
  "mail": {
    "transport": "SMTP",
    "from": "halfrost@halfrost.com",
    "options": {
	 "host": "smtp.qq.com",
     	 "secureConnection": true,
         "port": 465,
         "auth": {
              "user": "707176544@qq.com",
              "pass": "XXXX"
       	  }
     }
  },
  "database": {
    "client": "mysql",
    "connection": {
      "host": "127.0.0.1",
      "user": "ghost",
      "password": "XXXX",
      "database": "XXXX"
    }
  },
  "storage": {
    "active": "qn-store",
    "qn-store": {
      "accessKey": "XXXX",
      "secretKey": "XXXX",
      "bucket": "XXXX",
      "origin": "XXXX",
      "fileKey": {
        "safeString": true,
        "prefix": "[Blog/ArticleTitleImage/]",
	"suffix": "",
	"extname": true
      }
    }
  },
  "logging": {
    "transports": [
      "file",
      "stdout"
    ]
  },
  "process": "systemd",
  "paths": {
    "contentPath": "/var/www/ghost/content"
  }
}

The configuration fields above have changed a lot compared with older versions. Although the configuration options are basically the same, their format has changed.

You can configure email, the database, CDN storage, the log file path, and contentPath.

Testing

Start the current website service:

$ sudo systemctl start ghost_halfrost-com

Check the service status:

$ sudo systemctl status ghost_halfrost-com

● ghost_halfrost-com.service - Ghost systemd service for blog: halfrost-com
   Loaded: loaded (/var/www/ghost/system/files/ghost_halfrost-com.service; enabled; vendor preset: disabled)
   Active: active (running) since Sun 2018-07-15 14:40:07 CST; 8h ago
     Docs: https://docs.ghost.org
 Main PID: 454 (ghost run)
   Memory: 218.7M
   CGroup: /system.slice/ghost_halfrost-com.service
           ├─454 ghost run
           └─829 /usr/local/bin/node current/index.js

Note: Do not start it with ghost start; on CentOS 7, that command will fail because the service check returns unknown.

Use the bound domain name to access your site, and visit http://<domain>/ghost to register an administrator account.

If the site is accessible, configure the service to start on boot:

$ sudo systemctl enable ghost_halfrost-com

Issues Encountered

If you followed the steps above to upgrade Ghost and did not run into any issues, congratulations—you can happily leave this article now. If you did encounter problems, please keep reading.

Ghost officially provides a troubleshooting guide: troubleshooting. If you run into issues, you can check this guide first.

Next, I’ll share a few issues I encountered during the upgrade process.

node: command not found

This issue occurs after Ghost is installed. When a non-root user with sudo privileges invokes Node-related methods, this error appears.

$ sudo -u ghost node -v

sudo：node：command not found

When I ran into this issue, I was pretty confused. I had already created a non-root user with sudo privileges, and Node was installed globally. In theory, this problem shouldn’t have occurred. After searching online for quite a while, I finally found the cause.

It turns out that on CentOS, after Node is installed globally, the default path is /usr/local/bin/node, while Ghost may follow the Linux path convention and only look for /usr/bin/node. So you need to add a symlink to resolve this issue.

$ sudo ln -s /usr/local/bin/node /usr/bin/node

Check

$ sudo -u ghost node -v

v8.11.3

Successfully outputting the version number indicates success.

Server upload file size limit

For example, uploading a 10 MB high-resolution image will trigger an error because the server limits the file size. This limit is configured in nginx. The default is 5 MB; anything larger than that is not allowed.

So we need to increase the nginx limit. First, find the nginx configuration file. The configuration file is located at /etc/nginx/nginx.conf. (The original permissions of nginx.conf are -rw-r—r—, 0644.)

We need to modify the file permissions first:

$ cd /etc/nginx
$ chmod 777 nginx.conf

In this file, add client_max_body_size

$ vim nginx.conf

Add client_max_body_size 10m;

Finally, restore the file permissions and restart the nginx service.

$ chmod 644 nginx.conf
$ service nginx restart

user locked

When importing a JSON database backup from an older version of Ghost into the latest version of Ghost, you may run into an issue where the user is locked. This may be a security measure in Ghost.

I spent quite a while looking through the Ghost admin UI but couldn’t find anywhere to change this status directly. In the end, I found it in the database; after updating it there, everything worked.

$ mysql -u ghost -p

Enter password:

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 267
Server version: 5.7.37 MySQL Community Server (GPL)

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| ghost              |
| newghost           |
+--------------------+
3 rows in set (0.00 sec)

mysql> show tables;
+------------------------+
| Tables_in_newghost     |
+------------------------+
| accesstokens           |
| app_fields             |
| app_settings           |
| apps                   |
| brute                  |
| client_trusted_domains |
| clients                |
| invites                |
| migrations             |
| migrations_lock        |
| permissions            |
| permissions_apps       |
| permissions_roles      |
| permissions_users      |
| posts                  |
| posts_authors          |
| posts_tags             |
| refreshtokens          |
| roles                  |
| roles_users            |
| settings               |
| subscribers            |
| tags                   |
| users                  |
| webhooks               |
+------------------------+
25 rows in set (0.00 sec)

mysql> show create table users;
| users | CREATE TABLE `users` (
  `id` varchar(24) NOT NULL,
  `name` varchar(191) NOT NULL,
  `slug` varchar(191) NOT NULL,
  `ghost_auth_access_token` varchar(32) DEFAULT NULL,
  `ghost_auth_id` varchar(24) DEFAULT NULL,
  `password` varchar(60) NOT NULL,
  `email` varchar(191) NOT NULL,
  `profile_image` varchar(2000) DEFAULT NULL,
  `cover_image` varchar(2000) DEFAULT NULL,
  `bio` text,
  `website` varchar(2000) DEFAULT NULL,
  `location` text,
  `facebook` varchar(2000) DEFAULT NULL,
  `twitter` varchar(2000) DEFAULT NULL,
  `accessibility` text,
  `status` varchar(50) NOT NULL DEFAULT 'active',
  `locale` varchar(6) DEFAULT NULL,
  `visibility` varchar(50) NOT NULL DEFAULT 'public',
  `meta_title` varchar(2000) DEFAULT NULL,
  `meta_description` varchar(2000) DEFAULT NULL,
  `tour` text,
  `last_seen` datetime DEFAULT NULL,
  `created_at` datetime NOT NULL,
  `created_by` varchar(24) NOT NULL,
  `updated_at` datetime DEFAULT NULL,
  `updated_by` varchar(24) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `users_slug_unique` (`slug`),
  UNIQUE KEY `users_email_unique` (`email`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 |

There is a status field in the users table. Just change this field for the corresponding user to active.

mysql> update users set status = "active";

Emoji Upgrade

In older versions of Ghost, the database used utf8 encoding by default, so it could not support emoji. The latest version of Ghost creates tables with utf8mb4 encoding by default, which supports emoji. 🙄😏

Permission Issues

After installing the latest version of Ghost, there are still some additional issues, such as permission problems. Those just have to be resolved one by one.

$ ghost doctor

✔ Checking system Node.js version
✔ Checking logged in user
✔ Ensuring user is not logged in as ghost user
✔ Checking if logged in user is directory owner
✔ Checking current folder permissions
System checks failed with message: 'Linux version is not Ubuntu 16'
Some features of Ghost-CLI may not work without additional configuration.
For local installs we recommend using `ghost install local` instead.
? Continue anyway? Yes
ℹ Checking operating system compatibility [skipped]
✔ Checking for a MySQL installation
Running sudo command: systemctl is-active ghost_halfrost-com
✔ Validating config
✔ Checking folder permissions
✖ Checking file permissions
✖ Checking content folder ownership
✔ Checking memory availability
One or more errors occurred.

1) Checking file permissions

Message: Your installation folder contains some directories or files with incorrect permissions:
- ./content/themes/boo-master/assets/fonts/casper-icons.svg
- ./content/themes/boo-master/assets/fonts/casper-icons.woff
- ./content/themes/boo-master/assets/fonts/casper-icons.eot
- ./content/themes/boo-master/assets/fonts/casper-icons.ttf
- ./content/themes/yasuko-----2/author.hbs
- ./content/themes/yasuko-----2/default.hbs
- ./content/themes/yasuko-----2/LICENSE
- ./content/themes/yasuko-----2/gulpfile.js
- ./content/themes/yasuko-----2/page.hbs
- ./content/themes/yasuko-----2/assets/js/dev.min.js
- ./content/themes/yasuko-----2/assets/js/webfont.js
- ./content/themes/yasuko-----2/assets/js/jquery.fitvids.js
- ./content/themes/yasuko-----2/assets/js/prism.js
- ./content/themes/yasuko-----2/assets/js/lazy.js
- ./content/themes/yasuko-----2/assets/js/all.min.js
- ./content/themes/yasuko-----2/assets/js/index.js
- ./content/themes/yasuko-----2/assets/css/uncompressed.css
- ./content/themes/yasuko-----2/assets/css/dev.min.css
- ./content/themes/yasuko-----2/assets/css/all.min.css
- ./content/themes/yasuko-----2/assets/css/screen.css
- ./content/themes/yasuko-----2/assets/css/font_.min.css
- ./content/themes/yasuko-----2/index.hbs
- ./content/themes/yasuko-----2/partials/navigation.hbs
- ./content/themes/yasuko-----2/partials/loop.hbs
- ./content/themes/yasuko-----2/package.json
- ./content/themes/yasuko-----2/post.hbs
- ./content/themes/yasuko-----2/tag.hbs
- ./content/themes/yasuko-----2/README.md
- ./content/themes/odin-master/assets/fonts/casper-icons.svg
- ./content/themes/odin-master/assets/fonts/casper-icons.woff
- ./content/themes/odin-master/assets/fonts/casper-icons.eot
- ./content/themes/odin-master/assets/fonts/casper-icons.ttf
- ./content/themes/odin-master/assets/js/rrssb.min.js
- ./content/themes/odin-master/assets/css/rrssb.css
- ./node_modules/os-name/cli.js
- ./node_modules/mime/src/build.js
- ./node_modules/mime/cli.js
- ./node_modules/semver/bin/semver
- ./node_modules/osx-release/cli.js
- ./node_modules/mkdirp/bin/cmd.js
- ./node_modules/escodegen/bin/escodegen.js
- ./node_modules/escodegen/bin/esgenerate.js
- ./node_modules/esprima/bin/esvalidate.js
- ./node_modules/esprima/bin/esparse.js
Run sudo find ./ ! -path "./versions/*" -type f -exec chmod 664 {} \; and try again.


2) Checking content folder ownership

Message: Your installation folder contains some directories or files with incorrect permissions:
- ./content/adapters
- ./content/adapters/storage
- ./content/adapters/storage/qn-store
- ./content/adapters/storage/qn-store/LICENSE
- ./content/adapters/storage/qn-store/lib
- ./content/adapters/storage/qn-store/lib/getHash.js
- ./content/adapters/storage/qn-store/package.json
- ./content/adapters/storage/qn-store/index.js
- ./content/adapters/storage/qn-store/.npmignore
- ./content/adapters/storage/qn-store/README.md
Run sudo chown -R ghost:ghost ./content and try again.

Debug Information:
    OS: CentOS, v7.3.1611
    Node Version: v8.11.3
    Ghost-CLI Version: 1.8.1
    Environment: production
    Command: 'ghost doctor'

Try running ghost doctor to check your system for known issues.

Please refer to https://docs.ghost.org/v1/docs/troubleshooting#section-cli-errors for troubleshooting.

Judging from the errors, they are all caused by file permission issues.

$ sudo find ./ ! -path "./versions/*" -type f -exec chmod 664 {} \;
$ sudo chown -R ghost:ghost ./content

After changing the permissions, run ghost doctor again, and all issues should be resolved.

$ ghost doctor

✔ Checking system Node.js version
✔ Checking logged in user
✔ Ensuring user is not logged in as ghost user
✔ Checking if logged in user is directory owner
✔ Checking current folder permissions
System checks failed with message: 'Linux version is not Ubuntu 16'
Some features of Ghost-CLI may not work without additional configuration.
For local installs we recommend using `ghost install local` instead.
? Continue anyway? Yes
ℹ Checking operating system compatibility [skipped]
✔ Checking for a MySQL installation
Running sudo command: systemctl is-active ghost_halfrost-com
✔ Validating config
✔ Checking folder permissions
✔ Checking file permissions
✔ Checking content folder ownership
✔ Checking memory availability

Reference：

getting-started-guide cli-install
Install & Setup (production)
troubleshooting
Unlock Your Locked Ghost Account

GitHub Repo：Halfrost-Field

Follow: halfrost · GitHub

Source: https://halfrost.com/ghost_update/