Alright. I'm going to ask a question that may sound stupid...

I've been hearing a lot about Docker lately, and have looked at their
website, but I'm not positive I know what it is...

It almost sounds like it's a portable VM, where you can have your OS and whatever programs you want running inside. It is then portable, so another person could run the same program with the same OS and setup.

Am I even close to having a basic understanding of it?

Thanks for helping this old guy try to understand new technology... ;)


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Black Panther(RCS)
a.k.a. Dan Richter
Sysop - Castle Rock BBS
telnet://bbs.castlerockbbs.com
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The sparrows are flying again....

--- Mystic BBS v1.12 A43 2019/03/02 (Linux/64)
* Origin: Castle Rock BBS - bbs.castlerockbbs.com - (1337:3/111)

02 Jun 19 23:41, you wrote to all:

I've been hearing a lot about Docker lately, and have looked at their website, but I'm not positive I know what it is...

Great!

It almost sounds like it's a portable VM, where you can have your OS
and whatever programs you want running inside. It is then portable, so another person could run the same program with the same OS and setup.

Docker is kinda like a VM, but a little different. (I've not very good a simplyfying answers...)

Think of a docker "image" as an application. It really should be 1 application to 1 image, but that doesnt strickly need to be true. (EG: My MBSE image contains MBSE, makenl and my MYSTIC image contains mystic and some doors.) The image has EVERYTHING the application needs to run - you only need to configure it and, if appropriate, give it a place to store persistent data.

I often use the concept of LiveCD's and USB drives. The liveCD is, an enviornment that you can put into any machine (of the same architecture), and it will boot into an environment that you can use (even though a LiveCD, by nature is a read-only device). If you want to keep your data, you need to tell the liveCD where your USB stick is, and store your data on your USB stick, so that it survives the shutdown. You can now take your liveCD + USB stick to any machine and "continue on" from where you left off.

A docker image - is like a live CD (except it normally represent just a single app - but that doesnt strictly need to be true) and when you run it, it creates a "container". The "docker runtime" represents the OS portion of a live CD. Thus the container + your persistent data, is the app throughout the life of the app.

The great thing about docker, is that the image is guaranteed to be runnable on a docker enivornment (of the same architecture) - so my Mystic docker container (for intel) is guaranteed to run on an Intel docker enviornment (regardless of whether that docker environment is linux, mac, windows, etc).

I have created BBS containers that you are welcome to play with to learn - for both Intel and Pi.

...deon


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* Origin: Chinwag | MBSE in Docker on Pi (1337:2/100)

On 11 Jun 2019, Deon George said the following...

Howdy - sorry, cant believe I missed this!

No problem. I've been caught up in a couple other projects and got busy myself... :)

it, it creates a "container". The "docker runtime" represents the OS portion of a live CD. Thus the container + your persistent data, is the app throughout the life of the app.

Ok, that's making sense now. The docker image not only contains the
application you want, but a basic 'OS' as well. The 'docker runtime'
is like the connection between the actual OS and the application, so it will run on any OS with the same architecture.

Do I have that right?

I have created BBS containers that you are welcome to play with to learn
- for both Intel and Pi.

I might have to give it a shot. It sounds interesting.


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Black Panther(RCS)

--- Mystic BBS v1.12 A43 2019/03/02 (Linux/64)
* Origin: Castle Rock BBS - bbs.castlerockbbs.com - (1337:3/111)

<e17b6749$tqwnet.tqw.docker@mbse.bbs.leenooks.net> <f91b1bfa$tqwnet.tqw.docker@mbse.bbs.leenooks.net>
On 2019-06-10 09:26:21 +0000, Black Panther said:

it, it creates a "container". The "docker runtime" represents the OS portion of a live CD. Thus the container + your persistent data, is the app throughout the life of the app.

Ok, that's making sense now. The docker image not only contains the application you want, but a basic 'OS' as well. The 'docker runtime'
is like the connection between the actual OS and the application, so it will run on any OS with the same architecture.

Actually, the basic OS portion of it may not be correct. But if you
think of basic OS as system libraries, then yes, they are there.
Actually if you build a PC that could only run a single application
(ie: kernel+libraries+application), then the container is the libaries+application part.

I might have to give it a shot. It sounds interesting.

Yell out if you need help. It can be daunting at first, but once you
get the hang of it, I think it makes life a little easier.

I have some details on my website that might help you get started: https://chinwag.leenooks.net

....deon


--- MBSE BBS v1.0.7.12 (GNU/Linux-ARM)
* Origin: Chinwag (1337:2/100@tqwnet)