Docker and Kubernetes

(Kubernetes aka k8s)

Kubernetes CLI

KubeCtl CLI doc

Kubernetes cheat sheet

K8s CLI Cheat sheet

CLI Quick ref

Docker Compose Kubernetes Cheat sheet

Kubernetes - Contexts

src: Docker: Kubernetes - intro - CLI example

kubectl config get-contexts

kubectl config use-context docker-desktop

kubectl get nodes

kubectl config view

Kubernetes - Orchestration example - running Pods:

src: Docker Kubernetes orchestration - short CLI reference

kubectl apply -f pod.yaml

kubectl get pods

kubectl logs demo

kubectl delete -f pod.yaml

Deploy to Kubernetes

(Containerize, Kubernetize, run)

Containerize

Containerize your application - Create image getting-started

git clone https://github.com/docker/getting-started.git

cd getting-started\app

copy con Dockerfile

# syntax=docker/dockerfile:1

FROM node:18-alpine

WORKDIR /app

COPY . .

RUN yarn install --production

CMD ["node", "src/index.js"]

EXPOSE 3000

^Z

docker build -t getting-started .

rem docker run -dp 3000:3000 getting-started

rem start http://localhost:3000

Kubernetize and run

src: Deploy to Kubernetes

Deploy, list, check, remote:

kubectl apply -f bb.yaml

kubectl get deployments

kubectl get services

start http://localhost:30001/

kubectl delete -f bb.yaml

Convert Docker Compose to Kubernetes

CLI kompose

Converts docker-compose.yaml to kubernetes-service.yaml

Kubernetes Dashboard

Web UI Dashboard

Create sample user

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.7.0/aio/deploy/recommended.yaml

kubectl proxy

start http://localhost:8001/api/v1/namespaces/kubernetes-dashboard/services/https:kubernetes-dashboard:/proxy/

kubectl delete -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.7.0/aio/deploy/recommended.yaml

*

kubectl -n kubernetes-dashboard delete serviceaccount admin-user

kubectl -n kubernetes-dashboard delete clusterrolebinding admin-user

Kubernetes Dashboard - in Docker container (have not tested yet)

src: https://hub.docker.com/r/kubernetesui/dashboard

docker pull kubernetesui/dashboard

Namespaces

Namespaces intro

kubectl get namespaces

kubectl get namespaces --show-labels

Create DEV namespace:

kubectl create -f https://k8s.io/examples/admin/namespace-dev.json

Kubernetes config

src: StackOverflow

Config Example

--kubeconfig

KUBECONFIG=$HOME/.kube/config

~/.kube/config # Linux

%USERPROFILE%/.kube # Windows

Kubernetes config file

src: DevOpsCube: KubeConfig file

kubectl -n kube-system create serviceaccount devops-cluster-admin

Kubernetes short tutorial

Docker and Kubernetes at TutorialPoint

See also

*

Docker: Get started with Kubernetes - build docker k8s ready apps

Docker: Play with Kubernetes

Kubernetes - home

*

Kubernetes: deprecating Docker, switch to other containers (containerd or CRI-O) (Open Container Initiative)

Kubernetes: Dockershim deprecation FAQ

MS: Kubernetes vs Docker - cz

Docker limits cpu memory

Docker memory CPU limits (Windows)

for WSL2, create or open file:

%USERPROFILE%\.wslconfig

not: %HOMEPATH%\.wslconfig

Note: you have to save it in Linux LF (not Windows CRLF) mode

Add or update lines:

memory=3GB

processors=1

#kernel=C:\\temp\\myCustomKernel

#kernelCommandLine = vsyscall=emulate

swap=8GB

swapfile=C:\\temp\\wsl-swap.vhdx

pageReporting=true

#localhostforwarding=true

#nestedVirtualization=false

#debugConsole=true

src:

Microsoft Learn: example .wslconfig

src: Google search

StackOverflow: The Memory and CPU settings were removed for WSL2 integration

You have to stop all running WSL2 containers for changes to take effect.

Stop WSL2:

wsl --shutdown

SQL basic course základní kurz

SQL basic course základní kurz

Fakt pro začátečníky, žádný pokročilý věci.

SQL na českých stránkách:

https://www.google.com/search?q=sql+site%3Acz

Spousta kvalitních výukových materiálů úplně zdarma a česky:

https://www.itnetwork.cz/mysql/mysql-tutorial-uvod-a-priprava-prostredi

Tady je úplný úvod do SQL:

https://www.itnetwork.cz/mysql/mysql-tutorial-vytvoreni-databaze-a-tabulky

Nemusíš to zdlouhavě číst, to v černém rámečku jsou příkazy jazyka.

Vždy na konci článku je odkaz na další díl.

Obrázky jsou otisky obrazovky z pracovního prostředí, zde PhpMyAdmin, které je jedno z možných.

Pro znalost a práci s SQL žádné takové prostředí nepotřebuješ, stačí ti znát ty příkazy v černém rámečku.

Souhrn základních SQL příkazů:

CREATE DATABASE `it_school`;

DROP DATABASE `it_school`;

CREATE TABLE user (

    id int NOT NULL AUTO_INCREMENT PRIMARY KEY,

    title_before varchar(20),

    first_name varchar(20),

    last_name varchar(20),

    title_after varchar(20),

    birth_date date,

);

INSERT INTO `user`

    (`title_before`, `first_name`, `last_name`, `title_after`, `birth_date`)

    VALUES (`Ing.`, `Pavel`, `Dvorak`, `PhD.`, `2000-12-31`);

INSERT INTO `user`

    (`title_before`, `first_name`, `last_name`, `title_after`, `birth_date`)

    VALUES (`Mgr.`, `Karel`, `Sovak`, NULL, `2001-11-30`),

    VALUES (`Bc.`, `Jiri`, `Mlady`, NULL, `2002-10-29`),

    VALUES (NULL, `Pavel`, `Stary`, NULL, `2003-09-28`);

SELECT * FROM USER;

UPDATE `user` SET `title_after` = `Doc.` WHERE `id` = 1;

SELECT * FROM USER;

DELETE FROM `user` WHERE `id` = 1;

DELETE FROM `user` WHERE `id` IN (2, 3, 5);

JavaScript programming basics

Základy programování v JavaScriptu

Úkol pro tebe. Připravil jsem ti hotový mini-program v JavaScriptu s Fibonacciho posloupností. Mám 2 varianty, rozhodni, která je lepší. Můžeš to upravovat rovnou v prohlížeči, výsledek je hned vidět vpravo.

Pro tyhle začátky je úplně jedno, zda Java nebo JavaScript, jde o princip a tady rovnou vidíš výsledek v pravém panelu.

Hotový program:

Fibonacci sequence:

Recursion:

https://jsbin.com/gopemiloki/edit?js,output

For loop:

https://jsbin.com/nakavuhuli/edit?js,output

https://jsbin.com/mayalijowa/edit?js,output

Úkol:

1. Podívej se na program, 1. i 2. variantu

1.a. Která varianta je lepší a proč?

2. Zkus si to naprogramovat sám znova (uprostřed šedé menu File / Clone, ať si nepřepíšeš originál, kdyžtak je originál ještě v příloze tohohle mailu)

3. Zkus nějakou změnu, úpravu (menu File / Clone)

Úkol:

Co je lepší a proč?

Zkus si to upravit.

Odkazy:

Co je to rekurze (nečti to celý)

https://cs.wikipedia.org/wiki/Rekurze_(programov%C3%A1n%C3%AD)

JavaScript cyklus for:

https://www.w3schools.com/js/js_loop_for.asp

- nečti to, jen klepni na Try it Yourself a zkus si něco sám

IT basic course základní kurz

Základní kurzy IT

Fakt základ, ukázky, nic pro profíky!

Keywords:

IT basic course 

IT základní kurz

Content:

Odkazy, poznámky, příklady základních úvodů do IT, programování, správy systémů atd.

Občas se mě lidi ptají, jak se naučit něco z IT, tak shromažďuji pár základních poznámek, klíčových slov a odkazů.

Články:

Základy programování v JavaScriptu (můj příklad v JavaScriptu)

Úvody do SQL (česky a s příkladama)

Algoritmy:

Fibonacci heap - Fibonacci heap CZ

Spring Hibernate Microservices cheat sheet

Spring Hibernate Microservices 

Unsorted notes

Cheat sheet

REST:

REST tut

- Spring HATEOAS - no links, no REST

- Simple HATEOAS

Query Parameter vs URI Path - RequestParam vs PathVariable

- Optional values

RequestParam

- Map all params

NotFoundAdvice

- exception translation

DB:

EntityManager

- Transactional

JDBCTemplate

- named param queriess

- exceptions

- dataSource

- exception translation

MQ

RabbitMQ

amqp

Configuration

- define configuration

Etc

- ThreadPoolTaskExecutor = async exec

- Autowired Qualifier

- paid - overview Getting Started With Spring 5

- testing - Mockito how to do in java - Mockito baeldung crossroads - Mockito baeldung

- Good guides - crossroads

Git unplugged notes

Git unplugged notes

Rebase issue

# If someone rebases on public branch, after pull all others could see:

Your branch and 'origin/branch1' have diverged,

and have 2 and 3 different commits each, respectively.

Solution

git fetch origin

git reset --hard origin/main

src stackoverflow

Rebase issue

Your branch is ahead of 'origin/master' by 3 commits

Solution

git fetch -p # clean up local branches

git pull --rebase # pull and rebase my local commits on top of incoming

Better solution (unchecked)

Step 1 : git checkout branch1

Step 2 : git pull -s recursive -X theirs # merge strategies

Step 3 : git reset --hard origin/branch1

Rebase issue explained (long)

git rev-list --count --left-right branch1...upstream

git rev-list --count --left-right origin/master...HEAD

*

# to see if the local repository is ahead, push needed:

git rev-list origin..HEAD

# to see if the local repository is behind, pull needed:

git rev-list HEAD..origin

# if you have numbers for both, then the two repositories have diverged:

git rev-list --count --left-right origin/master...HEAD

src: stackoverflow

src: https://stackoverflow.com/a/40990959

src-long: https://stackoverflow.com/a/66981730

# squash - reset soft:

#git reset --soft master

git reset --soft origin/master

git add -A

git commit

git push --force

# squash - reset to merge-base:

git checkout branch1

git reset $(git merge-base master $(git branch --show-current))

git add -A

git commit

git push --force

# src: https://stackoverflow.com/questions/25356810/git-how-to-squash-all-commits-on-branch

# Note: git merge-base branch2 branch3

Squash

# squash - merge squash:

git checkout origin/master

git merge --squash origin/branch1

git commit

git push --force

Git branch_name vs refs

git show-ref origin/main

1. If $GIT_DIR/<refname> exists, that is what you mean (this is usually useful only for HEAD, FETCH_HEAD, ORIG_HEAD, MERGE_HEAD and CHERRY_PICK_HEAD);

2. refs/<refname> if it exists;

3. refs/tags/<refname> if it exists;

4. refs/heads/<refname> if it exists;

5.  refs/remotes/<refname> if it exists;

6. refs/remotes/<refname>/HEAD if it exists.

src: stackoverflow.com

Long aside: how this all works (read only if sufficiently curious) :

src: stackoverflow.com

Git server repository (docker git repo)

Alpine Git client

JKarlos Docker Git server

Gogs and Podman Git server

Gogs Git server

Gogs by Pirates - GitHub like Git server

Gitea in Docker - demo - github

GitColony docker server - obsolete

Git server:

Google it:

https://www.google.com/search?q=gnu+gpl+git+server

Git server list - wiki:

https://en.wikipedia.org/wiki/Git#Git_server

Gerrit:

Home: https://www.gerritcodereview.com/

Wiki: https://en.wikipedia.org/wiki/Gerrit_(software)

GitOlite:

https://gitolite.com/gitolite/index.html

Wiki says: External projects like gitolite, which provide scripts on top of git software to provide fine-grained access control.

*

FLOSS:

Gogs

Gitea = fork of Gogs

Git Web interface self-hosted:

https://www.google.com/search?q=git+web+interface+self-hosted

Options – list – good overview:

https://www.cyberciti.biz/open-source/github-alternatives-open-source-seflt-hosted/

GitLab = web git, “Confluence” wiki, “Jira” tracker

https://gitlab.com/gitlab-org/gitlab-foss

Gitea – community fork of Gogs:

https://gitea.io/

Savannah = GNU = free software foundation (FSF)

http://savannah.gnu.org/projects/administration

GitBucket – Open source

https://github.com/gitbucket/gitbucket

Gogs - self hosted Git:

https://gogs.io/

*

Awesome Selfhosted:

https://github.com/awesome-selfhosted/awesome-selfhosted

GitWeb:

https://git-scm.com/book/en/v2/Git-on-the-Server-GitWeb

*

BitBucket.org

GitHub.com

Git web UI – including proprietary and closed-source:

https://www.slant.co/topics/1440/~best-self-hosted-web-based-git-repository-managers

https://www.slant.co/topics/425/~best-git-web-interfaces

Lodě Sázava 2021 (FAV)

KDY / WHEN:

Neděle / Sunday

15. 8. 2021

9:00 – 18:00

TRASA / ROUTE:

Sázava

Sázava - mapy

*

VLAK / TRAIN:

from destination to start for car drivers

Kácov (dest) - Zruč n. S (start)

Kácov (dest) - Zruč n. S (start) - Friday 22

TRAIN WALK:

Zruc NS from Train to start Camp Rakosi

*

START:

Výdej lodí / issuing canoes: 9.00–10.00

Zruč nad Sázavou

Kemp Rákosí

Start - Google maps point

bisport premise ZrucNS

*

PŘESKOČIT / AVOID (pomalí / slow service):

Tůmův Chabeřický mlýn

*

ODBOČKA / FORK (suggested):

Želivka fork, short break, refreshment, crystal clear cold water

*

BREAK (doporučený / suggested):

Kemp Omaha - gallery

nice weir

good kiosk - sausages, local beer, pancakes, coffee

it was perfect on last summer, I hope they keep the quality

*

CÍL / END:

Kácov

Kácov rental - Google maps point

Sběr lodí / return canoes: 15.00–19.00

bisport premise Kacov

KDO / WHO:

2 MarS single

2 MaD + Smita

3 Petr + Tamara + Ráša

2 Jiří + tatínek

PÚJČOVNA / RENTAL:

Bisport Kácov s.r.o., Kácov 158

https://www.bisport.cz/pujcovna-lodi

Mail: info@bisport.cz

Tel: + 420 777 335 618

PLATBA / PAYMENT:

Č.Ú. / Account: ***

Zpráva / Message: Your Name, Sazava 2021

*

ČÁSTKA / AMOUNT:

MarS: 399 CZK

MaD: 399 CZK

Jiri 2-seats: 399 CZK

Petr 3-seats: 555 CZK

*

PÚV CENA / ORIG PRICE:

Vydra 2 seats: 420 CZK / 1 canoe

Rivera 3 seats: 585 CZK / 1 canoe

sleva / discount: 5%

PÚJČOVNA / RENTAL – others:

Dronte (na Sázavě outsourcuje přes BiSport)

Samba (Ohře Ondra K a Anička letos, asi i loni a dříve)

Půjčovna Samba – stejná

KEYWORDS:

Canoe kanoe kánoe Sázava Sazava 2021 FAV

Docker networking

Create bridge

docker network create -d bridge mars_bridge

Run container inside specific network (i.e. Redis and Redis CLI)

docker run --name some-redis --network mars_bridge --rm -d redis

docker run -it --network mars_bridge --rm redis redis-cli -h some-redis

Connect container to network

docker network connect mars_bridge some-redis

Disconnect container from network

docker network disconnect mars_bridge some-redis

List Docker networks

docker network ls

Remove Docker network

docker network rm mars_bridge

Remove all unused networks

docker network prune

Inspect Docker network

docker network inspect mars_bridge

Inspect with formatted output

docker inspect --format='{{json .NetworkSettings.Networks}}'  some-redis

docker inspect --format="{{json .NetworkSettings.Networks}}" some-redis

docker inspect --format="{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}" some-redis

Sources

Docker - networking containers

Docker Hub - Redis (as an example of Docker-networked container)

Docker notes unplugged

 My Docker notes - crossroads

Docker orchestration with Kubernetes k8s

My Docker Kubernetes k8s notes

Docker memory CPU limits (Windows)

My Docker limits - cpu memory notes

Docker network configuration

My Docker networking notes

src: docs.docker.com

Docker Swarm stack deploy

My Docker Swarm stack deployment notes

src: docs.docker.com

See also

My AWS - Amazon Web Services - notes

DockerCon 2021 - conference

PlayWithDocker - play, 101tut, lab, get started, training

AWS - Amazon Web Services - notes

AWS - Amazon Web Services - notes

My unsorted notes about AWS

AWS general xroad

Home

Console

* console FFT Frankfurt

CLI

Sign in

Trainings all

Trainings and Certifications blog post

aws.training site

10 miutes tutorials crossroad

10 min tut xroad

WordPress, ServerLess, React, Linux VM, MySQL, Static S3, PostgreSQL

Popular AWS - services crossroads

Free Tier, Elastic Beanstalk, DynamoDB, RDS (Relational Database Service), CloudFront, Glacier

LightSail

 - servers and services management console

 -  easily setup your service

LightSail tutorials home

LightSail home page

EC2

- Elastic Compute Cloud

EC2 pricing

EC2 get started - LAMP, Elastic, WordPress, etc

* WordPress 10 min tut

S3

- Simple Storage Service

S3 home

S3 get started

Lambda

 - serverless computing

Lambda home

Lambda - get started - crossroad

Lambda - resources

Lambda - build basic web app

* Lambda - ServerLess web app tutorial

* ServerLess with Lambda, API GateWay, Amplify, DynamoDB, Cognito