Backing up Jenkins configurations to S3

If you have worked with Jenkins for any extended length of time you quickly realize that the Jenkins server configurations can become complicated.  If the server ever breaks and you don’t have a good backup of all the configuration files, it can be extremely painful to recreate all of the jobs that you have configured.  And most recently if you have started using the Jenkins workflow libraries, all of your custom scripts and coding will disappear if you don’t back it up.

Luckily, backing up your Jenkins job configurations is a fairly simple and straight forward process.  Today I will cover one quick and dirty way to backup configs using a Jenkins job.

There are some AWS plugins that will backup your Jenkins configurations but I found that it was just as easy to write a little bit of bash to do the backup, especially since I wanted to backup to S3, which none of the plugins I looked at handle.  In genereal, the plugins I looked at either felt a little bit too heavy for what I was trying to accomplish or didn’t offer the functionality I was looking for.

If you are still interested in using a plugin, here are a few to check out:

Keep reading if none of the above plugins look like a good fit.

The first step is to install the needed dependencies on your Jenkins server.  For the backup method that I will be covering, the only tools that need to be installed are aws cli, tar and rsync.  Tar and rsync should already be installed and to get the aws cli you can download and install it with pip, from the Jenkins server that has the configurations you want to back up.

pip install awscli

After the prerequisites have been installed, you will need to create your Jenkins job.  Click New Item -> Freestyle and input a name for the new job.

jenkins job name

Then you will need to configure the job.

The first step will be figuring out how often you want to run this backup.  A simple strategy would be to backup once a day.  The once per day strategy is illustrated below.

backup periodically

Note the ‘H’ above means to randomize when the job runs over the hour so that if other jobs were configured they would try to space out the load.

The next step is to backup the Jenkins files.  The logic is all written in bash so if you are familiar it should be easy to follow along.

# Delete all files in the workspace
rm -rf *

# Create a directory for the job definitions
mkdir -p $BUILD_ID/jobs

# Copy global configuration files into the workspace
cp $JENKINS_HOME/*.xml $BUILD_ID/

# Copy keys and secrets into the workspace
cp $JENKINS_HOME/identity.key.enc $BUILD_ID/
cp $JENKINS_HOME/secret.key $BUILD_ID/
cp $JENKINS_HOME/secret.key.not-so-secret $BUILD_ID/
cp -r $JENKINS_HOME/secrets $BUILD_ID/

# Copy user configuration files into the workspace
cp -r $JENKINS_HOME/users $BUILD_ID/

# Copy custom Pipeline workflow libraries
cp -r $JENKINS_HOME/workflow-libs $BUILD_ID

# Copy job definitions into the workspace
rsync -am --include='config.xml' --include='*/' --prune-empty-dirs --exclude='*' $JENKINS_HOME/jobs/ $BUILD_ID/jobs/

# Create an archive from all copied files (since the S3 plugin cannot copy folders recursively)
tar czf jenkins-configuration.tar.gz $BUILD_ID/

# Remove the directory so only the tar.gz gets copied to S3
rm -rf $BUILD_ID

Note that I am not backing up the job history because the history isn’t important for my uses.  If the history IS important, make sure to add a line to backup those locations.  Likewise, feel free to modify and/or update anything else in the script if it suits your needs any better.

The last step is to copy the backup to another location.  This is why we installed aws cli earlier.  So here I am just uploading the tar file to an S3 bucket, which is versioned (look up how to configure bucket versioning if you’re not familiar).

export AWS_DEFAULT_REGION="xxx"
export AWS_ACCESS_KEY_ID="xxx"
export AWS_SECRET_ACCESS_KEY="xxx"

# Upload archive to S3
echo "Uploading archive to S3"
aws s3 cp jenkins-configuration.tar.gz s3://<bucket>/jenkins-backup/

# Remove tar.gz after it gets uploaded to S3
rm -rf jenkins-configuration.tar.gz

Replace the AWS_DEFAULT_REGION with the region where the bucket lives (typically us-east-1), make sure to update the AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY to use an account with access to write to AWS S3 (not covered here).  The final thing to note, <bucket> should be replaced to use your own bucket.

The backup process itself is usually pretty fast unless the Jenkins server has a massive amount of jobs and configurations.  Once you have configured the job, feel free to run it once to test if it works.  If the job worked and returns as completed, go check your S3 bucket and make sure the tar.gz file was uploaded.  If you are using versioning there should just be one file, and if you choose the “show versions” option you will see something similar to the following.

s3 backup

If everything went okay with your backup and upload to s3 you are done.  Common issues configuring this backup method are choosing the correct AWS bucket, region and credentials.  Also, double check where all of your Jenkins configurations live in case there aren’t in a standard location.

Liked it? Support me on Patreon

Josh Reichardt

Josh is the creator of this blog, a system administrator and a contributor to other technology communities such as /r/sysadmin and Ops School. You can also find him on Twitter and Facebook.