Jenkins pipeline (parallel && dynamically)?

Question

Question

I have simple parallel pipeline (see code) which I use together with Jenkins 2.89.2. Additionally I use parameters and now want to be able to in-/decrease the

Answer 1

Although the question assumes using declarative pipeline I would suggest to use scripted pipeline because it's way more flexible.
Your task can be accomplished this way

properties([
    parameters([
        string(name: 'countTotal', defaultValue: '3')
    ])
])

def stages = [failFast: true]
for (int i = 0; i < params.countTotal.toInteger(); i++) {
    def vmNumber = i //alias the loop variable to refer it in the closure
    stages["deployVM ${vmNumber}"] = {
        stage("deployVM ${vmNumber}") {
            sh "echo p1; sleep 12s; echo phase${vmNumber}"
        }
    }
}

node() {
    parallel stages
}

Also take a look at snippet generator which allows you to generate some scripted pipeline code.