I have a Jenkins controller running in VM and docker running on another VM, I have setup all the required things for making docker as a build-agent for Jenkins. Now When I am running a simple job on docker-build agent, I am getting following error:
SSHLauncher{host='192.168.33.15', port=49162, credentialsId='dock-cont-pass', jvmOptions='', javaPath='', prefixStartSlaveCmd='', suffixStartSlaveCmd='', launchTimeoutSeconds=60, maxNumRetries=10, retryWaitTime=15, sshHostKeyVerificationStrategy=hudson.plugins.sshslaves.verifiers.NonVerifyingKeyVerificationStrategy, tcpNoDelay=true, trackCredentials=true}
[08/02/21 11:00:36] [SSH] Opening SSH connection to 192.168.33.15:49162.
[08/02/21 11:00:36] [SSH] WARNING: SSH Host Keys are not being verified. Man-in-the-middle attacks may be possible against this connection.
[08/02/21 11:00:37] [SSH] Authentication successful.
[08/02/21 11:00:37] [SSH] The remote user's environment is:
BASH=/usr/bin/bash
BASHOPTS=checkwinsize:cmdhist:complete_fullquote:extquote:force_fignore:globasciiranges:hostcomplete:interactive_comments:progcomp:promptvars:sourcepath
BASH_ALIASES=()
BASH_ARGC=([0]="0")
BASH_ARGV=()
BASH_CMDS=()
BASH_EXECUTION_STRING=set
BASH_LINENO=()
BASH_SOURCE=()
BASH_VERSINFO=([0]="5" [1]="0" [2]="17" [3]="1" [4]="release" [5]="x86_64-pc-linux-gnu")
BASH_VERSION='5.0.17(1)-release'
DIRSTACK=()
EUID=1000
GROUPS=()
HOME=/home/jenkins
HOSTNAME=7bf4435f24c4
HOSTTYPE=x86_64
IFS=$' \t\n'
LOGNAME=jenkins
MACHTYPE=x86_64-pc-linux-gnu
MOTD_SHOWN=pam
OPTERR=1
OPTIND=1
OSTYPE=linux-gnu
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
PIPESTATUS=([0]="0")
PPID=72
PS4='+ '
PWD=/home/jenkins
SHELL=/bin/bash
SHELLOPTS=braceexpand:hashall:interactive-comments
SHLVL=1
SSH_CLIENT='192.168.33.10 37292 22'
SSH_CONNECTION='192.168.33.10 37292 172.17.0.3 22'
TERM=dumb
UID=1000
USER=jenkins
_=']'
Checking Java version in the PATH
openjdk version "1.8.0_292"
OpenJDK Runtime Environment (build 1.8.0_292-8u292-b10-0ubuntu1~20.04-b10)
OpenJDK 64-Bit Server VM (build 25.292-b10, mixed mode)
[08/02/21 11:00:37] [SSH] Checking java version of /jdk/bin/java
Couldn't figure out the Java version of /jdk/bin/java
bash: /jdk/bin/java: No such file or directory
[08/02/21 11:00:37] [SSH] Checking java version of java
[08/02/21 11:00:37] [SSH] java -version returned 1.8.0_292.
[08/02/21 11:00:37] [SSH] Starting sftp client.
ERROR: [08/02/21 11:00:37] [SSH] SFTP failed. Copying via SCP.
java.io.IOException: The subsystem request failed.
at com.trilead.ssh2.channel.ChannelManager.requestSubSystem(ChannelManager.java:741)
at com.trilead.ssh2.Session.startSubSystem(Session.java:362)
at com.trilead.ssh2.SFTPv3Client.<init>(SFTPv3Client.java:100)
at com.trilead.ssh2.SFTPv3Client.<init>(SFTPv3Client.java:119)
at com.trilead.ssh2.jenkins.SFTPClient.<init>(SFTPClient.java:43)
at hudson.plugins.sshslaves.SSHLauncher.copyAgentJar(SSHLauncher.java:688)
at hudson.plugins.sshslaves.SSHLauncher.access$400(SSHLauncher.java:111)
at hudson.plugins.sshslaves.SSHLauncher$1.call(SSHLauncher.java:456)
at hudson.plugins.sshslaves.SSHLauncher$1.call(SSHLauncher.java:421)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.io.IOException: The server denied the request.
at com.trilead.ssh2.channel.ChannelManager.requestSubSystem(ChannelManager.java:737)
... 12 more
[08/02/21 11:00:37] [SSH] Copying latest remoting.jar...
Expanded the channel window size to 4MB
[08/02/21 11:00:37] [SSH] **Starting agent process: cd "" && java -jar remoting.jar -workDir -jar-cache /remoting/jarCache
No argument is allowed: /remoting/jarCache**
java -jar agent.jar [options...]
-agentLog FILE : Local agent error log destination (overrides
workDir)
-auth user:pass : If your Jenkins is security-enabled, specify
a valid user name and password.
-cert VAL : Specify additional X.509 encoded PEM
certificates to trust when connecting to
Jenkins root URLs. If starting with @ then
the remainder is assumed to be the name of
the certificate file to read.
-connectTo HOST:PORT : make a TCP connection to the given host and
port, then start communication.
-cp (-classpath) PATH : add the given classpath elements to the
system classloader.
-failIfWorkDirIsMissing : Fails the initialization if the requested
workDir or internalDir are missing ('false'
by default) (default: false)
-help : Show this help message (default: false)
-internalDir VAL : Specifies a name of the internal files
within a working directory ('remoting' by
default) (default: remoting)
-jar-cache DIR : Cache directory that stores jar files sent
from the master
-jnlpCredentials USER:PASSWORD : HTTP BASIC AUTH header to pass in for making
HTTP requests.
-jnlpUrl URL : instead of talking to the master via
stdin/stdout, emulate a JNLP client by
making a TCP connection to the master.
Connection parameters are obtained by
parsing the JNLP file.
-loggingConfig FILE : Path to the property file with
java.util.logging settings
-noKeepAlive : Disable TCP socket keep alive on connection
to the master. (default: false)
-noReconnect : Doesn't try to reconnect when a
communication fail, and exit instead
(default: false)
-proxyCredentials USER:PASSWORD : HTTP BASIC AUTH header to pass in for making
HTTP authenticated proxy requests.
-secret HEX_SECRET : Agent connection secret to use instead of
-jnlpCredentials.
-tcp FILE : instead of talking to the master via
stdin/stdout, listens to a random local
port, write that port number to the given
file, then wait for the master to connect to
that port.
-text : encode communication with the master with
base64. Useful for running agent over 8-bit
unsafe protocol like telnet
-version : Shows the version of the remoting jar and
then exits (default: false)
-workDir FILE : Declares the working directory of the
remoting instance (stores cache and logs by
default) (default: -jar-cache)
Agent JVM has terminated. Exit code=0
[08/02/21 11:00:39] Launch failed - cleaning up connection
[08/02/21 11:00:39] [SSH] Connection closed.
How Can I resolved this problem I am using SSH-connection for connecting the docker container.
I have solved above problem by changing the username in dockerfile for build-agent, previously it was set to root user,now I have set this to jenkins and now Jenkins server will use "/home/jenkins/" as a working directory.
You need to build image from this dockerfile and then specify this particular image to the cloud-configuration of docker
You need to change the credentials in jenkins as well
FROM ubuntu:18.04
RUN mkdir -p /var/run/sshd
RUN apt -y update
RUN apt install -y openjdk-8-jdk
RUN apt install -y openssh-server
RUN apt install -y git
#RUN apt install -y maven
#generate the host keys with the default key file path, an empty passphrase
RUN ssh-keygen -A
ADD ./sshd_config /etc/ssh/sshd_config
RUN echo ***jenkins:password123***| chpasswd
RUN chown -R **jenkins:jenkins** /home/jenkins/
EXPOSE 22
CMD ["/usr/sbin/sshd", "-D"]