2019-05-12

Jenkins Linux agent configuration

Prepare Java runtime

Check if had installed java

$ java -version
openjdk version "1.8.0_65"
OpenJDK Runtime Environment (build 1.8.0_65-b17)
OpenJDK 64-Bit Server VM (build 25.65-b01, mixed mode)

if not Here is an article telling you how to install it

Create Node

1. Jenkins home page->Manage Node->New Node, such as window-build-machine

2. List Linux agent settings

Items	Settings
Name	Linux-build-machine
Description	used for Linux build
of executors	1
Remote root directory	/home/agent
Labels	Linux, build
Usage	Use this node as much as possible
Launch method	Launch agent agents via SSH
Host	192.168.1.112
Credentials	username/password
Host Key Verification Strategy	Manually trusted key Verification Strategy
Availability	Keep this agent online as much as paossible

3. How to set credentials

credentials	configuration
Domain	Global credentials (unrestricted)
Kind	Username with password
Scope	Global(Jenkins, nodes, items, all child items, etc)
Username	root
Password	mypassword
Description	Linux agent username & password

4. Save then Connect

Remoting version: 3.29
This is a Unix agent
Evacuated stdout
Agent successfully connected and online
SSHLauncher{host='192.168.1.112', port=22, credentialsId='d1cbab74-823d-41aa-abb7-8584859503d0', jvmOptions='', javaPath='/usr/bin/java',
prefixStartSlaveCmd='', suffixStartSlaveCmd='', launchTimeoutSeconds=210, maxNumRetries=10, retryWaitTime=15,
sshHostKeyVerificationStrategy=hudson.plugins.sshslaves.verifiers.ManuallyTrustedKeyVerificationStrategy, tcpNoDelay=true, trackCredentials=true}
[05/11/19 01:33:37] [SSH] Opening SSH connection to 192.168.1.112:22.
[05/11/19 01:33:37] [SSH] SSH host key matches key seen previously for this host. Connection will be allowed.
[05/11/19 01:33:37] [SSH] Authentication successful.
[05/11/19 01:33:37] [SSH] The remote user's environment is:

Troubleshooting

Problem	how to fix
[04/22/19 23:15:07] [SSH] WARNING: No entry currently exists in the Known Hosts file for this host. Connections will be denied until this new host and its associated key is added to the Known Hosts file.	ssh-keyscan HOSTNAME >> known_hosts
/var/lib/jenkins/.ssh/known_hosts [SSH] No Known Hosts file was found at /var/lib/jenkins/.ssh/known_hosts.	changing the Host key verification strategy in LAUNCH METHOD from “Known Hosts file verification strategy” to “Manually trusted key verification strategy”