Oozie SSH action Sample Oozie workflow that demonstrates the SSH action to move files from a specific node to HDFS

00-OozieSSHAction

This gist covers the Oozie SSH action.
It includes components of a sample Oozie workflow application- scripts/code, 
sample data and commands;  Oozie actions covered: secure shell action, email 
action.

My blog has documentation, and highlights of a very basic sample program.
http://hadooped.blogspot.com/2013/10/apache-oozie-part-13-oozie-ssh-action_30.html
 
 
This gist includes:
--------------------
Data and script download            
Data load commands                  
Shell script                        
Oozie job properties file          
Oozie workflow  file                
Oozie SMTP configuration            
Oozie commands                       
Output in HDFS
Output email                         
Oozie web console - screenshots  

My other blogs on Oozie:
------------------------
Blog 1: Oozie workflow - hdfs and email actions
Blog 2: Oozie workflow - hdfs, email and hive actions
Blog 3: Oozie workflow - sqoop action (Hive-mysql; sqoop export)
Blog 4: Oozie workflow - java map-reduce (new API) action
Blog 5: Oozie workflow - streaming map-reduce (python) action 
Blog 6: Oozie workflow - java main action
Blog 7: Oozie workflow - Pig action
Blog 8: Oozie sub-workflow
Blog 9a: Oozie coordinator job - time-triggered sub-workflow, fork-join control and decision control
Blog 9b: Oozie coordinator jobs - file triggered 
Blog 9c: Oozie coordinator jobs - dataset availability triggered
Blog 10: Oozie bundle jobs
Blog 11: Oozie Java API for interfacing with oozie workflows
Blog 12: Oozie workflow - shell action +passing output from one action to another

   

01-DataAndCodeDownload

************************************
*Data and code/application download
************************************
 
Data and code:
--------------
Github: 
https://github.com/airawat/OozieSamples
 
Email me at airawat.blog@gmail.com if you encounter any issues
 
 
Directory structure of application download
--------------------------------------------
 
  oozieProject
      workflowSshAction
         job.properties
         workflow.xml
      scripts
         uploadFile.sh
      data
         employees_data
        
         

02-Intent

************************************
*Intent of sample application
************************************

The application includes an Oozie worklow that runs an operation on a specific node 
leveraging Oozie ssh action.

Specifically:
It SSHs to a node specified in the workflow (cdh-dn01), and executes the command 
specified in the workflow (uploadFile.sh).  The command specified is a shell script 
local to the remote node - and it essentially copies a local file to HDFS.

The ssh action accepts arguments.  For simplicity, the same have not been included
in the sample program.

A pictorial representation of the workflow is at:
http://hadooped.blogspot.com/2013/10/apache-oozie-part-13-oozie-ssh-action_30.html

 

03-JobProperties

#*************************************************
#  job.properties
#*************************************************
 
nameNode=hdfs://cdh-nn01.chuntikhadoop.com:8020
jobTracker=cdh-jt01:8021
queueName=default
 
oozie.libpath=${nameNode}/user/oozie/share/lib
oozie.use.system.libpath=true
oozie.wf.rerun.failnodes=true
 
oozieProjectRoot=${nameNode}/user/${user.name}/oozieProject
appPath=${oozieProjectRoot}/workflowSshAction
oozie.wf.application.path=${appPath}

inputDir=${oozieProjectRoot}/data
focusNodeLogin=akhanolk@cdh-dn01
shellScriptPath=~/scripts/uploadFile.sh

emailToAddress=akhanolk@cdh-dev01

04-WorkflowXML

<!--******************************************-->
<!--workflow.xml                              -->
<!--******************************************-->
 
<workflow-app name="WorkFlowForSshAction" xmlns="uri:oozie:workflow:0.1">
    <start to="sshAction"/>
    <action name="sshAction">
        <ssh xmlns="uri:oozie:ssh-action:0.1">
            <host>${focusNodeLogin}</host>
	    <command>${shellScriptPath}</command>
            <capture-output/>
        </ssh>
	<ok to="sendEmail"/>
        <error to="killAction"/>
    </action>
    <action name="sendEmail">
        <email xmlns="uri:oozie:email-action:0.1">
              <to>${emailToAddress}</to>
              <subject>Output of workflow ${wf:id()}</subject>
              <body>Status of the file move: ${wf:actionData('sshAction')['STATUS']}</body>
        </email>
        <ok to="end"/>
        <error to="end"/>
    </action>
    <kill name="killAction">
        <message>"Killed job due to error"</message>
    </kill>
    <end name="end"/>
</workflow-app>

05-ShellScript

#################################
# Name: uploadFile.sh
# Location: remote node where we
#           want to run an 
#           operation
#################################
#!/bin/bash

hadoop fs -rm -R oozieProject/results-sshAction/*
hadoop fs -put ~/data/* oozieProject/results-sshAction/

status=$?

if [ $status = 0 ]; then
	echo "STATUS=SUCCESS"
else
	echo "STATUS=FAIL"
fi

06-LocationForFiles

*****************************************
Location of files/scripts & commands
*****************************************

I have pasted information specific to my environment;  Modify as required.

1) Node (cdh-dev01) where the Oozie CLI will be used to submit/run Oozie workflow:

Structure/Path:
~/oozieProject/workflowSshAction/job.properties

2) HDFS:

Workflow directory structure:
/user/akhanolk/oozieProject/workflowSshAction/workflow.xml

Commands to load:
hadoop fs -mkdir oozieProject
hadoop fs -mkdir oozieProject/workflowSshAction
hadoop fs -put ~/oozieProject/workflowSshAction/workflow.xml oozieProject/workflowSshAction

Output directory structure:
/user/akhanolk/oozieProject/results-sshAction

Command:
hadoop fs -mkdir oozieProject/results-sshAction

3) Remote node (cdh-dn01) where we want to run a shell script:

Directory structure/Path:
~/scripts/uploadFile.sh
~/data/employee_data

07-ExpectedResult

*********************************
Expected Result
*********************************
File, uploadFile.sh, at ~/scripts, on cdh-dn01 should get loaded to HDFS at -
/user/akhanolk/oozieProject/results-sshAction

08a-OozieSMTPConfiguration

Oozie SMTP configuration
------------------------
Add the following to the oozie-site.xml, and restart oozie.
Replace values with the same specific to your environment.
 
<!-- SMTP params-->
<property>
  <name>oozie.email.smtp.host</name>
  <value>cdh-dev01</value>
</property>
<property>
  <name>oozie.email.smtp.port</name>
  <value>25</value>
</property>
<property>
  <name>oozie.email.from.address</name>
  <value>oozie@cdh-dev01</value>
</property>
<property>
  <name>oozie.email.smtp.auth</name>
  <value>false</value>
</property>
<property>
  <name>oozie.email.smtp.username</name>
  <value></value>
</property>
<property>
  <name>oozie.email.smtp.password</name>
  <value></value>
</property>

08b-SSHSetup

************************
SSH setup
************************
Issues:
Review my section on issues encountered to see all the issues and fixes I had to make
to get the workflow application to work.

------------------------------------------------------------------------------------------------------
Oozie documentation:
To run SSH Testcases and for easier Hadoop start/stop configure SSH to localhost to be passphrase-less.
Create your SSH keys without a passphrase and add the public key to the authorized file:

$ ssh-keygen -t dsa
$ cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys2
Test that you can ssh without password:

$ ssh localhost
------------------------------------------------------------------------------------------------------
SSH tutorial:
Setup ssh - https://www.digitalocean.com/community/articles/how-to-set-up-ssh-keys--2

09-OozieCommands

Oozie commands
---------------
Note: Replace oozie server and port, with your cluster-specific.
 
1) Submit job:
$ oozie job -oozie http://cdh-dev01:11000/oozie -config oozieProject/workflowSshAction/job.properties -submit
job: 0000012-130712212133144-oozie-oozi-W
 
2) Run job:
$ oozie job -oozie http://cdh-dev01:11000/oozie -start 0000014-130712212133144-oozie-oozi-W
 
3) Check the status:
$ oozie job -oozie http://cdh-dev01:11000/oozie -info 0000014-130712212133144-oozie-oozi-W
 
4) Suspend workflow:
$ oozie job -oozie http://cdh-dev01:11000/oozie -suspend 0000014-130712212133144-oozie-oozi-W
 
5) Resume workflow:
$ oozie job -oozie http://cdh-dev01:11000/oozie -resume 0000014-130712212133144-oozie-oozi-W
 
6) Re-run workflow:
$ oozie job -oozie http://cdh-dev01:11000/oozie -config oozieProject/workflowSshAction/job.properties -rerun 0000014-130712212133144-oozie-oozi-W
 
7) Should you need to kill the job:
$ oozie job -oozie http://cdh-dev01:11000/oozie -kill 0000014-130712212133144-oozie-oozi-W
 
8) View server logs:
$ oozie job -oozie http://cdh-dev01:11000/oozie -logs 0000014-130712212133144-oozie-oozi-W
 
Logs are available at:
/var/log/oozie on the Oozie server.

10-Output

************************
Output
************************

[akhanolk@cdh-dev01 ~]$ hadoop fs -ls oozieProject/res*
Found 1 items
-rw-r--r--   3 akhanolk akhanolk   13821993 2013-10-30 20:59 oozieProject/results-sshAction/employees_data

11-OutputEmail

********************
Output email
********************
From akhanolk@cdh-dev01.localdomain  Wed Oct 30 22:59:16 2013
Return-Path: <akhanolk@cdh-dev01.localdomain>
X-Original-To: akhanolk@cdh-dev01
Delivered-To: akhanolk@cdh-dev01.localdomain
From: akhanolk@cdh-dev01.localdomain
To: akhanolk@cdh-dev01.localdomain
Subject: Output of workflow 0000003-131029234028597-oozie-oozi-W
Content-Type: text/plain; charset=us-ascii
Date: Wed, 30 Oct 2013 22:59:16 -0500 (CDT)
Status: R

Status of the file move: SUCCESS

12-OozieScreenshots

************************************
Oozie web console screenshots
************************************

Available at:
http://hadooped.blogspot.com/2013/10/apache-oozie-part-13-oozie-ssh-action_30.html

13-IssuesEncountered

*************************
Issues encountered
*************************

Permissions denied error:
-------------------------
....
2013-10-29 16:13:25,949 WARN org.apache.oozie.command.wf.ActionStartXCommand: 
USER[akhanolk] GROUP[-] TOKEN[] APP[WorkFlowForSshAction] JOB[0000002-
131029144918199-oozie-oozi-W] ACTION[0000002-131029144918199-oozie-oozi-
W@sshAction] Error starting action [sshAction]. ErrorType [NON_TRANSIENT], 
ErrorCode [AUTH_FAILED], Message [AUTH_FAILED: Not able to perform operation 
[ssh -o PasswordAuthentication=no -o KbdInteractiveDevices=no -o 
StrictHostKeyChecking=no -o ConnectTimeout=20 akhanolk@cdh-dn01  
mkdir -p oozie-oozi/0000002-131029144918199-oozie-oozi-W/sshAction--ssh/ ] 
| ErrorStream: Permission denied (publickey,gssapi-keyex,gssapi-with-mic,password).


Steps taken to resolve:
-----------------------
a)
Tried running the command in square brackets, above, manually from cdh-dev01 (Oozie server), 
when logged in as akhanolk.  It worked!  But the worklow in Oozie didnt;

b)
Tried running as Oozie-
sudo -u oozie ssh -o PasswordAuthentication=no -o KbdInteractiveDevices=no -o 
StrictHostKeyChecking=no -o ConnectTimeout=20 akhanolk@cdh-dn01 mkdir 
-p oozie-oozi/0000001-1310081859355-oozie-oozi-W/action1--ssh/

Got the error
Permission denied (publickey,gssapi-keyex,gssapi-with-mic,password).

c)
Googled - and chanced upon this-
http://stackoverflow.com/questions/19272430/oozie-ssh-action

So, performed the necessary actions detailed below to allow oozie to ssh to cdh-dn01 as akhanolk
On cdh-dev01 (my Oozie server), located the oozie home directory and ran ssh keygen
Appended the public key to authorized_keys file home/akhanolk/.ssh/authorized_keys on cdh-dev01
Appended the same public key to authorized_keys file in cdh-dn01 (remote node) at 
home/akhanolk/.ssh/authorized_keys

Issue resolved!!

That is very helpful. Thank for your guide :) :) :)