If you recently installed Sonatype Nexus and have started using it to support internal development and collaboration, you will likely want to know how to configure backups to capture your configuration files and repository data. Any system as central to your development effort as a repository manager needs to be backed up on a daily basis. Hard drives and power supplies fail, and critical repository artifacts in a hosted repository may be inadvertently deleted.
In this post, I go through the recommended procedures for backing up a Sonatype Nexus installation. I discuss which files and directories need to be backed up, and I make some specific recommendations about backup configuration. Luckily, Sonatype Nexus was designed to use the filesystem to store both configuration and repository data. This means that backing up your Sonatype Nexus installation is as easy as configuring an automated backup tool such as amanda or a simple backup script that uses rsync. There is no database to export or server to suspend for the duration of the backup. Backing up or restoring a Sonatype Nexus installation is as easy as copying a set of files.
When you installed Sonatype Nexus, two directories were created. An application directory (nexus-professional-1.4.1/) and a Sonatype Work directory (sonatype-work/). The application directory contains all of the executable files and libraries that comprise the Sonatype Nexus application, and the Sonatype Work directory contains all of the installation-specific configuration and repository data for your own installation of Sonatype Nexus. If you have modified the configuration of Sonatype Nexus, that configuration is stored in sonatype-work/. If you've uploaded artifacts to hosted repositories, customized repository metadata, or proxied artifacts from remote repositories, all of that data is going to be stored in sonatype-work/. In this blog post, we are going to focus on this sonatype-work/ directory as it contains all of the data we need to back up.
Note: If you have deployed Sonatype Nexus as a WAR in your own servlet containter. The sonatype-work/ folder should be under the user home directory by default. If you have deployed Sonatype Nexus using the standard distribution (embedded Jetty), the sonatype-work/ directory will be a sibling to the Sonatype Nexus application directory.
If you have the disk space to spare, you can simply back up the whole sonatype-work/ directory. If you are looking for more detail about what is and is not critical to back up, this section will detail the contents of the sonatype-work/ directory from a backup perspective. Some of the files in this sonatype-work/ directory are critical while other files can be easily regenerated if they are lost. Here is a full list of subfolders, from the most important to least:
Now that you know what to back up. I will describe the process I use to back up my own instance of Sonatype Nexus. I don't use a fancy automated back up tool like amanda that can make incremental backups on remote storage. I simply use rsync and copy the resulting backup to a removable disk. My Sonatype Nexus installation is running on Ubuntu Linux, and the path of sonatype-work directory is /home/juven/bin/sonatype-work/. I have a removable disk which is mounted at /media/disk/, and I am using rsync to make backups of sonatype-work/ each night:
$ rsync -a --delete -v ~/bin/sonatype-work /media/disk/
The options I pass to rsync are:
This command will back up the whole sonatype-work/ folder. What if I only want to back up some important the sub-folders? To do this, I create an rsync includes file that lists the directories and file patterns I want rsync to include in my backup:
+ /sonatype-work/nexus/storage/ + /sonatype-work/nexus/storage/releases/ + /sonatype-work/nexus/storage/thirdparty/ + /sonatype-work/nexus/conf/ + /sonatype-work/nexus/logs/ + /sonatype-work/nexus/timeline/ - /sonatype-work/nexus/storage/* - /sonatype-work/nexus/*
This tells rsync to only include what we want, and exclude anything else, now run rsync again with the includes list:
$ rsync -a --delete -v --include-from includes.list \ ~/bin/sonatype-work /media/disk/
If your backup disk is always connected to your machine and you don’ t want to repeat the backup command manually, schedule a task to run the backup periodically. On Linux, cron is a perfect tool for automating the backup task. To configure the backup job, edit /etc/crontab, add a line like this (you would change juven to an appropriate username on your own system):
0 0 * * 0 juven rsync -a --delete \ --include-from ~/bin/includes.list ~/bin/sonatype-work /media/disk/
This entry tells cron to run the rsync command as user juven once a week. That's all there is to it.