Google Group Post Link: https://groups.google.com/forum/#!topic/jenkinsci-dev/p3HzZkvLNFo

summary:

When jenkins builds finished, the background processes would be killed at the same time.

I search the Internet, people say using "BUILD_ID=dontKillMe"(see -----JENKINS-14442-----) can slove the problem. but this feature only works on FREESTYLE BUILD . When I using  PIPELINE BUILD, that problem shows up again.

For testing, I tried servial combinations and get following results.

withenv:
Jenkins Version: 2.32.3 /  2.60.1
JAVA Version: 1.8.0_121
TOMCAT Version(for jenkins): 9.0.0.M17
SLAVE OS : Red Hat Enterprise Linux Server release 6.4 (Santiago) 
 
test situations:

1、JENKINS Master OS : CentOS6.8 / RedHat5.6 ， Background processes can keep alive without setting "BUILD_ID=dontKillMe"。

2、JENKINS Master OS : RedHat6.4  , using A FREESTYLE BUILD with "BUILD_ID=dontKillMe" , Background processes can keep alive。

3、⭐JENKINS Master OS : RedHat6.4  , using A PIPELINE BUILD with "BUILD_ID=dontKillMe" , Background processes always be killed 。

guess:

Due to backgroud processes can keep running on specific OS like CentOS6.8 / RedHat5.6 without using "BUILD_ID=dontKillMe" feature, and "BUILD_ID=dontKillMe" do works on FREESTYLE BUILD. 

1、Backgroud processes being killed or not depends on Jenkins Master OS version? Is there any rules? 

2、Maybe  pipeline's sh step not support "BUILD_ID=dontKillMe" feature? IF its ture , i hope this feature can be support in future.