Docker Container 101

Virtualization or hypervisor virtualizes hardware; docker container virtualizes OS kernel.

First, we just start a docker images with Multipass.

PS> multipass launch docker -n kiko

Login to docker and start download the images.

PS> multipass shell kiko

ubuntu@kiko:~$ docker pull centos

ubuntu@kiko:~$  docker container run -itd --name cc centos

ubuntu@kiko:~$ docker exec -it cc bash 

[root@a4d5e22b6ef5 /]# cat /etc/os-release

Try download other images.

ubuntu@kiko:~$ docker pull archlinux 

ubuntu@kiko:~$ docker pull ubuntu

ubuntu@kiko:~$ docker pull almalinux

ubuntu@kiko:~$ docker run -itd --name uu ubuntu

Check the utilization and stop the container.

ubuntu@kiko:~$ docker stats

ubuntu@kiko:~$ docker stop uu cc 

 

Why container runs so fast and why use container?

• share the kernel with hosts (compare to separate guest OS kernel).
  
• use control group to define cpu, mem, disk, network namespaces.
• container is portable.
• micro-service concept.
  

Links:

• Docker 101
  

Docker and VM

There are many comparison between Docker and Virtual Machine in term of architecture. 

Here're some summary on operational between Docker and Virtual Machine, based on my own understanding.

	VM	Docker
Compatibility	👍	👌
Virtualization	👍	👌
Security	👍	👌
Size	👌	👍
Performance	👌	👍
Scalability	👌	👍

 

Windows Virtual Machines

Here're the 2 ways to actually get a pre-made Windows Virtual Machine directly from Microsoft. Note that this isn't a permanent solution. 

The first is the Microsoft Edge Developer page under Tools and then VMS. You can choose between Windows 8, 8.1, and 10. For VM platform, we can choose between VirtualBox, Vagrant, VMware, HyperV, and Parallels (Mac).

For Windows 11 VM, we need to head over to the Windows 11 development environment page. Again, we can choose between 4 different virtualization software options. Note the expiration date!

Microsoft recommends to save a "snapshot" of the VM. But this only works for the first method.

Links:

• https://developer.microsoft.com/en-us/microsoft-edge/tools/vms/
• https://developer.microsoft.com/en-us/windows/downloads/virtual-machines/
• How to Legally Download a Windows Virtual Machine

Lab21 Architecture Design

I have been deciding on the virtualization tools for my Lab21 between VMWare Player and VirtualBox. Both have advantages on their own. 

There are 3 types of networking in virtualization tools: NAT, host-only, and bridged.

1. NAT - Most commonly used. 
2. Host-only - Mostly for private used.
3. bridged - For advanced user only.
   

While doing my research on which tools to use, I come across an interesting video run OpenWrt router image on a VirtualBox with "host-only + bridged" environment. 

After watching the video, it gives me more ideas about how to design Lab21 architecture.

Links:

• OpenWrt on VirtualBox HowTo
• OpenWrt on x86 hardware
• https://downloads.openwrt.org/releases/21.02.1/targets/x86/64/ 
  

Linux OS for Lab21

I have shortlisted a few Linux distributions for Lab21 project. Namely a few are:

• Ubuntu Desktop 20.04
• Ubuntu Server 20.04
• AlmaLinux 8.5
• Rocky Linux 8.5

Other Linux distribution that are still under consideration:

• Kali Linux
• Fedora Linux
• Centos Linux
  

Virtualization options:

• VMWare Workstation for Player
• VirtualBox
  

New Tool: Disk2vhd v1.0

>>> Sent via Google Reader:

New Tool: Disk2vhd v1.0
via Sysinternals Site Discussion by curtismetz on 10/7/09

Disk2vhd v1.0: We're excited to announce a new Sysinternals tool, Disk2vhd, that simplifies the migration of physical systems into virtual machines (p2v). Just run Disk2vhd on the system you want to migrate and specify the volumes for which you want data included, and Disk2vhd creates a consistent point-in-time volume snapshot followed by an export of the selected volumes into one or more VHDs that you can add to a new or existing Hyper-V or Virtual PC virtual machine.

Linux LiveCD on Windows

MobaLiveCD is a freeware that will run your Linux LiveCD on Windows thanks to the excellent emulator called "Qemu".

MobaLiveCD allows you to test your LiveCD with a single click : after downloading the ISO image file of your favorite LiveCD, you just have to start it in MobaLiveCD and here you are, without the need to burn a CD-Rom or to reboot your computer.

MobaLiveCD key features:

• No need to burn the CD-Rom anymore
• Program without installation that you can start from an USB stick
• A clear and easy to use interface
• Light and portable application, packaged in a single executable of 1.6MB only

Link:

• http://mobalivecd.mobatek.net/en/

VMware Server 2 is Available

The Vmware Server 2.0 is available for download now.

With VMware Server 2, the new features offer increased performance and stability. You benefit from:

• A broader range of guest operating system support.
  
• Direct access to virtual machine consoles.
  
• Intuitive Web-based management interface.
  
• More memory for greater scalability, from 3.6 GB to 8.0 GB of RAM per virtual machine.

File Extension in VMware

Some well-known file extensions used in VMware.

.VMDK -- These files are the actual hard disk of the virtual machine itself, and tend to be the largest file within the folder. You can consider the size of this file to be roughly equivalent to the size of either the disk itself (if you've chosen to use preallocated disks) or the size of the data currently stored on that disk (if you use growable disks).

.NVRAM -- Consider this file the BIOS of the virtual machine.

.VMX -- With typically one VMX file per folder, this file holds the configuration information for the virtual machine in a text format. Unlike almost all the other files you'll see, these files can be edited using any text editing program, a process that is actually required for some functionality that is not exposed in the GUI.

.VMXF -- This file, in XML format, includes additional information about the virtual machine if it has been added to a team. If a machine has been added to a team and then later removed, this file remains resident. This file can also be opened and read in a text editor.

.VMTM -- For virtual machines actively participating in a team, this file stores information about that team membership.

.VMEM -- These files, which contain a backup of the VMs paging file, are typically very small or non-existent when the virtual machine is powered off, but grow immediately to the size of configured RAM when the machine is powered on.

.VMSN and .VMSD -- When snapshots are created for a virtual machine, these files are created to host the state of the virtual machine. The VMSN file stores the running state of the machine, what you could consider the "delta" between the VMDK at the point of the snapshot and what has been processed up until the present time. The VMSD stores information and metadata about the snapshot itself.

.VMSS -- If you've suspected the state of your machine, this file contains the suspended state of that machine. These files typically only appear when virtual machines have been suspended.

>>> http://mcpmag.com/columns/article.asp?editorialsid=2708

The Only True Drop-in MS-Exchange Alternative

Just come across this solution from the web, which claims to provide plugin-free interoperability with Microsoft Exchange server. This PostPath Server is a Linux-based enterprise-class email and collaboration server. It is the only drop-in, natively interoperable alternative to Microsoft Exchange.

From the documentation, it seems impressive. It has 4 lines of product:

1. PostPath Server
2. PostPath Webmail
3. PostPath Vmware Edition
4. PostPath Archive Edition
   

The PostPath Server™ incorporates code from several open source projects. They do make modifications to that open source code and is available for download. If you are interested in downloading these modifications, give it a try at PPSD Open Source Modifications, ftp://ftp.postpath.com/pub/OpenSource/.

The Challenge of Virtualization Security

This is one of the excellent articles that I've seen this year. It is great, and it tells the root cause for most of the problems we faced nowadays.

The real problem of security in a virtualization world is not technical, it is organizational and operational.

With the consolidation of applications, operating systems, storage, information, security and networking -- all virtualized into a single platform rather than being discretely owned, managed and supported by (reasonably) operationally-mature teams -- the biggest threat we face in virtualization is now we have lost not only visibility, but the clearly-defined lines of demarcation garnered from a separation of duties we had in the non-virtualized world.

See the full article at:
>>> http://rationalsecurity.typepad.com/blog/2008/03/the-challenge-o.html