Problems in Jenkins Guided tour on Mac - macos

Question

I just downloaded Jenkins using brew and I installed Docker CE.
When I try to execute the pipeline in the Guided Tour:
pipeline {
agent { docker 'maven:3.3.3' }
stages {
stage('build') {
steps {
sh 'mvn --version'
}
}
}
}
the build fails with the following error:
/Users/C0228983/.jenkins/workspace/POC_develop-6BCMWWG26VSSPB6S7LLDJWBDCIGFTA2YRE63L5XCEQAEMWYYDVTQ#tmp/durable-cc73be26/script.sh: line 2: docker: command not found
As you see docker in not available in the $PATH.
How could I modify the $PATH? are there more things to consider in order to install jenkins on a Mac an use Docker agent?
After a manual update of $PATH in the Jenkinsfile another error appear:
java.io.IOException: Cannot run program "docker": error=2, No such file or directory
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
at hudson.Proc$LocalProc.<init>(Proc.java:245)
at hudson.Proc$LocalProc.<init>(Proc.java:214)
at hudson.Launcher$LocalLauncher.launch(Launcher.java:846)
at hudson.Launcher$ProcStarter.start(Launcher.java:384)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.launch(DockerClient.java:268)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.launch(DockerClient.java:249)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.launch(DockerClient.java:246)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.version(DockerClient.java:218)
at org.jenkinsci.plugins.docker.workflow.WithContainerStep$Execution.start(WithContainerStep.java:136)
at org.jenkinsci.plugins.workflow.cps.DSL.invokeStep(DSL.java:184)
at org.jenkinsci.plugins.workflow.cps.DSL.invokeMethod(DSL.java:126)
at org.jenkinsci.plugins.workflow.cps.CpsScript.invokeMethod(CpsScript.java:108)
at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.call(PogoMetaClassSite.java:48)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)
at com.cloudbees.groovy.cps.sandbox.DefaultInvoker.methodCall(DefaultInvoker.java:18)
at org.jenkinsci.plugins.docker.workflow.Docker$Image.inside(jar:file:/Users/C0228983/.jenkins/plugins/docker-workflow/WEB-INF/lib/docker-workflow.jar!/org/jenkinsci/plugins/docker/workflow/Docker.groovy:128)
at org.jenkinsci.plugins.docker.workflow.Docker.node(jar:file:/Users/C0228983/.jenkins/plugins/docker-workflow/WEB-INF/lib/docker-workflow.jar!/org/jenkinsci/plugins/docker/workflow/Docker.groovy:63)
at org.jenkinsci.plugins.docker.workflow.Docker$Image.inside(jar:file:/Users/C0228983/.jenkins/plugins/docker-workflow/WEB-INF/lib/docker-workflow.jar!/org/jenkinsci/plugins/docker/workflow/Docker.groovy:116)
at org.jenkinsci.plugins.pipeline.modeldefinition.agent.impl.DockerPipelineScript.runImage(jar:file:/Users/C0228983/.jenkins/plugins/pipeline-model-definition/WEB-INF/lib/pipeline-model-definition.jar!/org/jenkinsci/plugins/pipeline/modeldefinition/agent/impl/DockerPipelineScript.groovy:54)
at org.jenkinsci.plugins.pipeline.modeldefinition.agent.impl.AbstractDockerPipelineScript.configureRegistry(jar:file:/Users/C0228983/.jenkins/plugins/pipeline-model-definition/WEB-INF/lib/pipeline-model-definition.jar!/org/jenkinsci/plugins/pipeline/modeldefinition/agent/impl/AbstractDockerPipelineScript.groovy:68)
at org.jenkinsci.plugins.pipeline.modeldefinition.agent.impl.AbstractDockerPipelineScript.run(jar:file:/Users/C0228983/.jenkins/plugins/pipeline-model-definition/WEB-INF/lib/pipeline-model-definition.jar!/org/jenkinsci/plugins/pipeline/modeldefinition/agent/impl/AbstractDockerPipelineScript.groovy:54)
at org.jenkinsci.plugins.pipeline.modeldefinition.agent.CheckoutScript.checkoutAndRun(jar:file:/Users/C0228983/.jenkins/plugins/pipeline-model-extensions/WEB-INF/lib/pipeline-model-extensions.jar!/org/jenkinsci/plugins/pipeline/modeldefinition/agent/CheckoutScript.groovy:57)
at org.jenkinsci.plugins.pipeline.modeldefinition.agent.CheckoutScript.doCheckout(jar:file:/Users/C0228983/.jenkins/plugins/pipeline-model-extensions/WEB-INF/lib/pipeline-model-extensions.jar!/org/jenkinsci/plugins/pipeline/modeldefinition/agent/CheckoutScript.groovy:40)
at org.jenkinsci.plugins.pipeline.modeldefinition.agent.impl.LabelScript.run(jar:file:/Users/C0228983/.jenkins/plugins/pipeline-model-definition/WEB-INF/lib/pipeline-model-definition.jar!/org/jenkinsci/plugins/pipeline/modeldefinition/agent/impl/LabelScript.groovy:44)
at ___cps.transform___(Native Method)
at com.cloudbees.groovy.cps.impl.ContinuationGroup.methodCall(ContinuationGroup.java:57)
at com.cloudbees.groovy.cps.impl.FunctionCallBlock$ContinuationImpl.dispatchOrArg(FunctionCallBlock.java:109)
at com.cloudbees.groovy.cps.impl.FunctionCallBlock$ContinuationImpl.fixArg(FunctionCallBlock.java:82)
at sun.reflect.GeneratedMethodAccessor229.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.cloudbees.groovy.cps.impl.ContinuationPtr$ContinuationImpl.receive(ContinuationPtr.java:72)
at com.cloudbees.groovy.cps.impl.ClosureBlock.eval(ClosureBlock.java:46)
at com.cloudbees.groovy.cps.Next.step(Next.java:74)
at com.cloudbees.groovy.cps.Continuable.run0(Continuable.java:154)
at org.jenkinsci.plugins.workflow.cps.SandboxContinuable.access$001(SandboxContinuable.java:18)
at org.jenkinsci.plugins.workflow.cps.SandboxContinuable$1.call(SandboxContinuable.java:33)
at org.jenkinsci.plugins.workflow.cps.SandboxContinuable$1.call(SandboxContinuable.java:30)
at org.jenkinsci.plugins.scriptsecurity.sandbox.groovy.GroovySandbox.runInSandbox(GroovySandbox.java:108)
at org.jenkinsci.plugins.workflow.cps.SandboxContinuable.run0(SandboxContinuable.java:30)
at org.jenkinsci.plugins.workflow.cps.CpsThread.runNextChunk(CpsThread.java:165)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup.run(CpsThreadGroup.java:330)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup.access$100(CpsThreadGroup.java:82)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup$2.call(CpsThreadGroup.java:242)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup$2.call(CpsThreadGroup.java:230)
at org.jenkinsci.plugins.workflow.cps.CpsVmExecutorService$2.call(CpsVmExecutorService.java:64)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at hudson.remoting.SingleLaneExecutorService$1.run(SingleLaneExecutorService.java:112)
at jenkins.util.ContextResettingExecutorService$1.run(ContextResettingExecutorService.java:28)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.io.IOException: error=2, No such file or directory
at java.lang.UNIXProcess.forkAndExec(Native Method)
at java.lang.UNIXProcess.<init>(UNIXProcess.java:247)
at java.lang.ProcessImpl.start(ProcessImpl.java:134)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
at hudson.Proc$LocalProc.<init>(Proc.java:245)
at hudson.Proc$LocalProc.<init>(Proc.java:214)
at hudson.Launcher$LocalLauncher.launch(Launcher.java:846)
at hudson.Launcher$ProcStarter.start(Launcher.java:384)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.launch(DockerClient.java:268)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.launch(DockerClient.java:249)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.launch(DockerClient.java:246)
at org.jenkinsci.plugins.docker.workflow.client.DockerClient.version(DockerClient.java:218)
at org.jenkinsci.plugins.docker.workflow.WithContainerStep$Execution.start(WithContainerStep.java:136)
at org.jenkinsci.plugins.workflow.cps.DSL.invokeStep(DSL.java:184)
at org.jenkinsci.plugins.workflow.cps.DSL.invokeMethod(DSL.java:126)
at org.jenkinsci.plugins.workflow.cps.CpsScript.invokeMethod(CpsScript.java:108)
at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.call(PogoMetaClassSite.java:48)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)
at com.cloudbees.groovy.cps.sandbox.DefaultInvoker.methodCall(DefaultInvoker.java:18)
... 29 more
Versions:
osx 10.11.6
docker: 17.03.1-ce, build c6d412e
jenkins-lts: stable 2.46.2 (homebrew)

Answer 1

I just found the solution for the missing paths in $PATH but not for the IOException:
Go to Jenkins -> Manage Jenkins -> Configure System -> Global Properties
Activate Environment variables
Add a new one:
Name: PATH
Value: /usr/local/sbin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin
Docker was installed in: /usr/local/bin/