Month: September 2020

update jenkins timezone

There many ways to update jenkins timezone

Verify:

cat /etc/timezone
cat ls -ltr /etc/localtime
date

Centos/Redhat:

#update /etc/sysconfig/jenkins

#JENKINS_JAVA_OPTIONS="-Dorg.apache.commons.jelly.tags.fmt.timeZone=Asia/Calcutta"
#JENKINS_JAVA_OPTIONS="-Duser.timezone=Asia/Calcutta"

Debian/ubuntu :

#update /etc/default/jenkins

JAVA_ARGS="-Dorg.apache.commons.jelly.tags.fmt.timeZone=Asia/Calcutta"
JAVA_ARGS="-Duser.timezone=Asia/Calcutta"

Jenkins script console:


System.setProperty('user.timezone', 'Asia/Calcutta')
System.setProperty('org.apache.commons.jelly.tags.fmt.timeZone', 'Asia/Calcutta')

Check tcp port with BASH and CURL

WHY?
– If telnet command is not present on system
– Easy to use

BASH:

ECHO:

#1
echo > /dev/tcp/192.168.0.183/22

#2
echo > /dev/tcp/192.168.0.183/22 && echo "open"

#3
echo > /dev/tcp/192.168.0.183/22 && echo "open" || echo "close"

#4
(echo > /dev/tcp/192.168.0.183/22)  > /dev/null 2>&1 && echo "open" || echo "close"

CAT:

cat < /dev/tcp/192.168.0.183/22

CURL:

curl -v telnet://192.168.0.183:22
curl -v telnet://hackfi.initedit.com:80

Install metric server in kubernetes

WHY?
– Get node CPU/RAM usages
– Can create Horizontal Pod Autoscaler (HPA)
– Light weight

git clone https://github.com/kubernetes-sigs/metrics-server.git
  • Edit metrics-server/manifests/base/deployment.yaml and add below lines to args
args:
          - --cert-dir=/tmp
          - --secure-port=4443
          - --kubelet-preferred-address-types=InternalIP,Hostname,InternalDNS,ExternalDNS,ExternalIP
          - --kubelet-use-node-status-port #Deprecated metrics-server:v0.3.7
          - --kubelet-insecure-tls

kubectl apply -f metrics-server/manifests/base
  • To get node metrics run kubectl get top node

Jenkins skip stages using git branch name regex


def git_url = 'https://github.com/initedit/simple-storage-solution.git'
def git_branch = 'master'

pipeline
{
    agent
    {
        label 'master'
    }

    stages
    {
        stage('skip1')
        {
            when {
            expression {
                        echo git_branch
                        isDev = !(git_branch =~ /^dev*([a-zA-Z0-9]*)/)
                        return isDev
                       }
            }
            steps{
                   echo "if dev branch it will skip"
               }
        
        }
    }
}

Regex:
^dev*([a-zA-Z0-9]* = Start with dev
dev*([a-zA-Z0-9]* = contains dev

More : https://e.printstacktrace.blog/groovy-regular-expressions-the-definitive-guide/