Month: December 2021

Docker vs Podman

Docker vs Podman

Daemon

Podman has no daemon, which can run under normal user.

Docker has daemon dockerd running as root.

Unix socket

Docker uses Unix socket /var/run/docker.sock

All the REST API commands are implemented using this socket.

For example,


`docker version` command is implemented via following API.

curl --unix-socket /var/run/docker.sock http:/v2/version



## References

[Watch on Captionz
what is podman vs docker (beginner - intermediate) anthony explains](https://youtu.be/lkg5QJsoCCQ)

Upgrade Windows 10 to 11 Manually

Upgrade Windows 10 to 11 Manually

One of my PCs wasn't prompted for Windows 11 upgrade, but upgrade check passed.

Download

Windows 11 Installation Assistant can be downloaded from https://www.microsoft.com/en-au/software-download/windows11.

Install

To trigger manual upgrade, need to download Installation Assistant.

Troubleshooting

Got error when first time ran Installation Assistant. Error code #800070079. Then reboot to fix the issue.

References

How to upgrade a compatible PC to Windows 11 from Windows 10

Learning – Jekyll

Learning - Jekyll

Developers describe Jekyll as "Blog-aware, static site generator in Ruby". It is classified as "Static Site Generators" and "Self-Hosted Blogging / CMS", similar to WordPress for blogging.

Pros

  • Simple - No more databases, file based.
  • Static - Markdown (or Textile), Liquid templating language, HTML & CSS, etc.
  • Blog-aware - Includes permalinks, categories, pages, posts, and custom layouts.
  • Theme - Can be downloaded from rubygem
  • Github - Integration allow publish to Github

Cons

  • No search, but it is SEO friendly
  • No plugin
  • No image resizing
  • No tag

Installation

Both Ruby and Gem need to be installed.

gem install jekyll bundler

Verify

jekyll -v

Create a Site

jekyll new ga_blog

Then there is ga_blog folder created.

Launch the Site

For the first time, run

bundle exec jekyll serve

Subsquence time

jekyll serve

Then the website can be accessed from http://localhost:4000/

Folder structure

The _posts folder hosts posts.

The _site folder hosts the finial product of website.

Front Matter

Content

___
layout: post
title: "Welcome To Jekyll!"
date: 2017-09-24 15:58:59 -0700
categories: jekyll update
___

URL

http://localhost:4000/jekyll/update/2017/09/24/welcome-to-jekyll!.html

Also can create custom attribute in Front Matter.

Writing Posts

The posts can be in subfolders too, the URL will add subfolder in the path.

Filename format

_posts/2017-09-24-my-first-blog-post.md

Layout

layout: "post"

Overwrite

title: "This is the new title"
date: 2017-09-20 15:58:59 -0700

Drafts

Create folder called _drafts, and save draft posts in this folder with name only, the date will be the today's date.

my-draft-blog-post.md

Then run following command

jekyll serve --draft

Pages

Create page in root folder, such as donate.md, and set layout as page

layout: "page"

Then the URL will be

http://localhost:4000/donate

Premalinks

permalink: "/my-new-url/"

or

permalink: /:categories/:year/:month/:day/:title.html

Default Front Matter

Defined in _config.yml file

defaults:
  -
    scope:
      path: ""
      type: "posts"
    values:
      layout: "post"
      title: "My Title"

Then restart jekyll server.

Theme

Default theme is minima, other themes can be downloaded from https://rubygems.org, and search jekyll-theme.

Update Gemfile

gem: "jekyll-theme-hacker"

Then stop Jekyll server and run command

bundle install

Update _config.yml file

theme: jekyll-theme-hacker

Then start jekyll server using following command

bundle exec jekyll serve

If there is no output on the page, normally, it is because no layout defined in theme.

Layouts

Create <layout_name>.html in _layouts folder

<h1>This is page</h1>
<hr>

{{ content }}

Define sub layout, then can be used in other layout.

For example, in post.html layout

---
layout: wrapper
---

<h1>This is a post</h1>
<hr>

{{ content }}

Then it will use wrapper layout defined in wrapper.htm below

<html>
<head>
  <meta charset="UTF-8">
  <title>Doument</title>
</head>
<body>
  Wrapper <br>
  {{ content }}
  <br> Wrapper
</body>
</html>

Use this method for other layouts, then can have html skeleton.

Variables

Front Matter variables

{{ layer.author}}
{{ page.title }}
{{ page.author }}
{{ site.title }}

The site values are from _config.yml file

Other variables can be found in https://jekyllrb.com/docs/variables/.

Includes

Create a folder called _includes

Create a file called header.html in _includes folder as below

<h1>{{ site.title }}</h1>

Then update wrapper.html file

<html>
<head>
  <meta charset="UTF-8">
  <title>Doument</title>
</head>
<body>
  {% include header.html %}
  {{ content }}
</body>
</html>

Then every page using wrapper.html will use header.html to display header.

To define variable during include as below

{% include header.html color="blue" %}

Then access in header.html file as below

<h1 style="color: {{ include.color }}">{{ site.title }}</h1>

Looping Through Posts

Update _layouts/home.html

{% for post in site.posts %}
  <li><a href="{{ post.url }}">{{ post.title }}</a></li>
{% endfor %}

Conditionals

{% if page.title == ... %}
{% elsif page.title == ... %}
{% else %}
{% endif %}

For example

{% for post in site.posts %}
  <li><a style="{% if page.url == post.url %}color:red;{% endif %}" href="{{ post.url }}">{{ post.title }}</a></li>

Data file

Create a folder called _data, put YAML, JSON or CSV files in it.

For example, people.yml file

- name: "Mike"
  occupation: "Giraffe Academy"

- name: "Steve"
  occupation: "Firefighter"

...

In home.html file

{{ site.data.people }}

or

{% for person in site.data.people %}
  {{ person.name }}, {{ person.occupation }} <br>
{% endfor %}

Static Files

Those files have no Front Matter, can be stored in any folder. For example, in assets folder, in home.html file,

{% for file in site.static_files %}
  {{ file.path }} <br>
{% endfor %}

Configure Front Matter in _config.yml file

defaults:
  - scope:
      path: "assets/img"
    values:
      image: true

Then restart jekyll server

Update home.html file

{% for file in site.static_files %}
  {% if file.image %}
    <img src="{{ file.path }}" alt="{{ file.name }}">
  {% endif %}
{% endfor %}

Hosting on Github Pages

Create repository called ga_blog, and don't init with README.

Update _config.yml file

baseurl: "ga_blog"

Then

git init
git checkout -b gh-pages
git add .
git commit -m "initial commit"

Add remote repo

git remote add origin https://github.com/<name>/ga_blog.git

Push

git push origin gh-pages

Then go to setting in Github page, find out published URL

References

Tutorials

Download Let’s Encrypt intermediate certificate

Download Let's Encrypt intermediate certificate

In case required, the intermediate certificate can be downloaded from https://letsencrypt.org/certificates/.

The intermediate certificate will be renewed every 5 years as they mentioned.

References

Chain of Trust
Let's Encrypt's New Root and Intermediate Certificates

Migrate TrueNAS VM to Proxmox VM

Migrate TrueNAS VM to Proxmox VM

After Proxmox installed, I also migrate TrueNAS VM to Proxmox as VM for both Ubuntu VM and Windows 10 VM.

Copy zvol to a file and transfer to Proxmox server

The zpool volume device is located in /dev/zvol/<zpool_name>/<zvol_name>. Create disk image using following command.

dd if=/dev/zvol/pool0/server-xxxxxx of=/tmp/server.raw bs=8m
scp ...

Another way to transfer

dd if=/dev/zvol/.... bs=8192 status=progress | ssh root@proxmox 'dd of=....raw bs=8192'

or

dd if=/dev/zvol/.... bs=8192 status=progress | gzip -1 - | ssh root@proxmox 'dd of=....raw.gz bs=8192'

or

dd if=/dev/zvol/.... bs=8192 status=progress | gzip -1 - | ssh root@proxmox 'gunzip - | dd of=....raw.gz bs=8192'

Transfer raw file into Proxmox server

Create Proxmox VM

  • Create a VM with OVMF (UEFI) if TrueNAS VM is using UEFI

  • Remove VM disk

  • Use following command to import disk

qm importdisk <vm_id> <raw_file> <storage_id>

For example

qm importdisk 100 vm.raw ds1812-vm_nfs1
  • Go to VM hardware page

  • Select unused disk and click Add button to add disk into VM

    • For Linux, select SCSI as controller
    • For Windows, select SATA
  • Select Options => Boot Order to check the iscsi/sata controller

Boot TrueNAS VM

References

Export Virtual Machine from TrueNAS and Import VM to Proxmox
Migration of servers to Proxmox VE
Additional ways to migrate to Proxmox VE

Add PAM user in Proxmox as Admin

Add PAM user in Proxmox

Create user in OS

groupadd <group>
adduser -g <group> <user>
passwd <user>
mkdir ~<user>
chown <user>:<group> ~<user>

Add OS user to Proxmox

pveum user add <user>@pam
pveum user list

Add role to user

pveum acl modify <PATH> --roles PVEAdmin --users <user>@pam

For example

acl modify / --roles PVEAdmin --users user@pam

References

Add pam user to pve admin group?
users cant change own passwords
User Management

Usable Image with Different Size in WordPress

Usable Image with Different Size in WordPress

I was trying to find out the available pictures for same image in WordPress to enable fast download of small pictures in same page.

There are many pictures in different size, they can be found in WordPress html folder. Depending on the media configuration, maybe in different location. Here, only lists default location.

Location

The resized images files are in html/wp-content/uploads/<year>/<month> directory as the format of <picture_name>-<width>x<height>.jpg.

URL

Original image

Can be found at bottom Edit Media page as <picture_name>.jpg.

Scaled image

Can be found in text box File URL as <picture_name>-scaled.jpg

Other size images

Can change the scaled image URL to <picture_name>-<width>x<height>.jpg