Uncategorized – Page 9

Jenkins parameter and stash

pipeline {
    agent {label 'master'}
    parameters { 
    string(name: 'string1', defaultValue: 's1', description: 's1') 
    choice(name: 'CHOICES', choices: ['one', 'two', 'three'], description: 'chose') 
    password(name: 'password', defaultValue: 'SECRET', description: 'password')
    }
    stages{
        stage('one'){
            steps{
                sh "echo abc > abc.txt"
                stash includes: 'abc.txt', name: 'abc'
                sh "rm -rf abc.txt"
            }
        }
        stage('two'){
            steps{
                unstash 'abc'
                sh "cat abc.txt"
            }
        }
    }
}

https://www.jenkins.io/doc/book/pipeline/syntax/#parameters

Jenkins stash and unstash

pipeline {
    agent {label 'master'}
    stages{
        stage('one'){
            steps{
                sh "echo abc > abc.txt"
                stash includes: 'abc.txt', name: 'abc'
                sh "rm -rf abc.txt"
            }
        }
        stage('two'){
            steps{
                unstash 'abc'
                sh "cat abc.txt"
            }
        }
    }
}

Open port using NC command in linux

Open port using NC:

nc 8888

Listen port:

nc localhost 8888

Send packet using bash:

echo -n "hello" >/dev/tcp/localhost/8888

Mount cifs/samba share inside container

#Dockerfile
FROM ubuntu
RUN apt update -y
RUN apt install  cifs-utils -y

docker build -t cifs .

docker run -it --cap-add SYS_ADMIN --cap-add DAC_READ_SEARCH   -cap-add NET_BIND_SERVICE cifs bash

#centos with privileged (working)

docker run --privileged -it --cap-add SYS_ADMIN --cap-add DAC_READ_SEARCH --cap-add NET_BIND_SERVICE centos bash

mount -t cifs -o username=a,password=a //192.168.0.228/public /mnt

mount -t cifs -o username=a,password=a //192.168.0.228/public /mnt

mount -t cifs -o username=a,password=a,ro,domain=WORKGROUP //192.168.0.228/public /a -v

Get aws ec2 instance id from shell/bash

cat /sys/devices/virtual/dmi/id/board_asset_tag

#short hostname
hname=$(cat /sys/devices/virtual/dmi/id/board_asset_tag | awk '{print substr($0,5,15)}')
hostnamectl set-hostname $hname

Mysql allow from all – Test

CREATE USER 'root'@'%' IDENTIFIED BY 'Test#123';

GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION;

Jenkins questions list

install jenkins using docker-compose
default port for jenkins 8080
Explain the your CICD pipeline
What is DSL?
How do you manage credentials in jenkins?
explain the basic structure of Jenkinsfile?
how jobs are managed for different branch/ multibranch?
What issues you faced in jenkins? = plugin high disk IO
build trigger?
how to configure webhook?
poll SCM?
light checkout in jekins?
groovy sandbox?
add worker node in jenkins? types of method?

Disk IO read/write monitor

yum install sysstat -y

iostat -t

iostat -xtc

iostat -d

#More command

iostat -dx /dev/sda 5
sar
vmstat
badblock

Sonatype Nexus3 – Docker compose

version: '3'
services:
  jenkins:
    image: sonatype/nexus3:3.29.0
    user: root:root
    restart: always
    container_name: nexus
    environment:
      TZ: "Asia/Kolkata"
    volumes:
      - /opt/nexus-data:/nexus-data
    ports:
      - 8081:8081

Get admin passwords:

docker exec -it nexus bash

find / -iname admin.*

#OR

docker exec -it nexus  cat /nexus-data/admin.password

More : https://hub.docker.com/r/sonatype/nexus3#user-content-persistent-data

Nomad – Container orchestration example for Dev environment

#Install nomad

-Download the stable release form https://www.nomadproject.io/downloads

wget https://releases.hashicorp.com/nomad/1.0.1/nomad_1.0.1_linux_amd64.zip

unzip nomad_1.0.1_linux_amd64.zip

mv nomad /usr/local/bin/

#start nomad in dev mode

nomad agent -dev

nomad node status

#Install docker https://docs.docker.com/engine/install/centos/

yum-config-manager \
    --add-repo \
    https://download.docker.com/linux/centos/docker-ce.repo

yum install docker-ce docker-ce-cli containerd.io

systemctl start docker
systemctl enable docker

#Create simple nginx job file (nginx.nomad)

job "nginx" {
  datacenters = ["dc1"]
  type = "service"

  update {
    max_parallel = 1
    min_healthy_time = "10s"
    healthy_deadline = "3m"
    progress_deadline = "10m"
    auto_revert = false

    canary = 0
  }
  migrate {
    max_parallel = 1
    health_check = "checks"
    min_healthy_time = "10s"
    healthy_deadline = "5m"
  }
  group "cache" {
    count = 1

    network {
      port "nginx-port" {
        to = 80
      }
    }

    service {
      name = "nginx-port"
      tags = ["nginx", "web"]
      port = "nginx-port"

    }

    restart {
      attempts = 2
      interval = "30m"
      delay = "15s"
      mode = "fail"
    }

    ephemeral_disk {
      size = 300
    }


    task "nginx" {
      driver = "docker"

      config {
        image = "nginx"
        ports = ["nginx-port"]
      }

      resources {
        cpu    = 500
        memory = 256
      }

    }
  }
}

#Nomand commands for Run,Stop, job status and logs

nomad job status

nomad job run nginx.nomad

nomad job stop nginx

nomad job status nginx

nomad alloc status <Allocations ID>

nomad alloc logs <Allocations ID>

#Access webUI at http://127.0.0.1:4646