Nexus3 Backup and Recovery tool

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Backup or Migrate an entire Nexus Artifact Server

Download all artifacts at once or migrate automatically from Nexus to Nexus.

Although the Nexus backup and restore documentation indicates that one could backup and restore Nexus, the data seems not to be restored completely as 500 errors occur when an artifact is downloaded from the UI after restore. It could also be possible that some steps were not issued as they have should been. Apart from that, the restore is capable of restoring the Nexus configuration.

N3DR excludes the backup of group repositories and is able to backup all Maven2 and NPM repositories and migrate and/or restore Maven2 artifacts to another Nexus server.

Note: uploads to proxy and snapshot repositories are not supported by Nexus itself. As a workaround one could create a hosted repository in Nexus and upload the backed up proxy content to it.

The aims of the n3dr tool are:



snap install n3dr

Check the downloaded artifacts:

sudo ls /tmp/snap.n3dr/tmp/n3dr/download<some number, e.g.: 082028764>
sudo cp -r /tmp/snap.n3dr/tmp/n3dr/download<some number, e.g.: 082028764> /home/${USER}/n3dr-backup
sudo chown $USER:$USER -R /home/${USER}/n3dr-backup


Get the darwin artifact from the releases tab.


choco install n3dr


N3DR download user

Create a user, e.g. n3dr-download in Nexus3, create a role, e.g. n3dr-download and assign the following roles:

N3DR upload user

In order to upload artifacts, additional privileges are required:



Check the help menu

user@computer:~/dev$ n3dr -h
N3DR is a tool that is able to download all artifacts from
a certain Nexus3 repository.

  n3dr [command]

Available Commands:
  backup       Backup all artifacts from a Nexus3 repository
  help         Help about any command
  repositories Count the number of repositories or return their names
  upload       Upload all artifacts to a specific Nexus3 repository

  -v, --apiVersion string        The Nexus3 APIVersion, e.g. v1 or beta
                                 (default "v1")
  -d, --debug                    Enable debug logging
  -h, --help                     help for n3dr
      --insecureSkipVerify       Skip repository certificate check
  -p, --n3drPass string          The Nexus3 password
  -n, --n3drURL string           The Nexus3 URL
  -u, --n3drUser string          The Nexus3 user
  -z, --zip                      Add downloaded artifacts to a ZIP archive
      --directory-prefix string  The directory prefix is the directory where
                                 artifacts will be saved

Use "n3dr [command] --help" for more information about a command.


It is possible to load a custom CA to connect to Nexus3 if one created self-signed certificates, by using:


Note: store the ca.crt in the ~/.n3dr directory.


In order to download as a anonymous user, one has to use the --anonymous option.


Create an admin user

n3dr configUser \
  --email=some-admin-user@some-admin-user.some-admin-user \
  --firstName=some-admin-user \
  --lastName=some-admin-user \
  --pass=some-admin-user \
  --id=some-admin-user \
  --admin \
  -p <admin-pass> \
  -u <admin-user> \

Create a downloadUser

n3dr configUser \
  --email=some-admin-user@some-admin-user.some-admin-user \
  --firstName=some-admin-user \
  --lastName=some-admin-user \
  --pass=some-admin-user \
  --id=some-admin-user \
  --downloadUser \
  -p <admin-pass> \
  -u <admin-user> \

Create a uploadUser

n3dr configUser \
  --email=some-admin-user@some-admin-user.some-admin-user \
  --firstName=some-admin-user \
  --lastName=some-admin-user \
  --pass=some-admin-user \
  --id=some-admin-user \
  --uploadUser \
  -p <admin-pass> \
  -u <admin-user> \

Change a user pass

n3dr configUser \
  --email=admin@example.org \
  --firstName=admin \
  --lastName=admin \
  --pass=some-other-admin-pass \
  --id=admin \
  --changePass \
  -p <admin-pass> \
  -u <admin-user> \

Delete a repository

n3dr configRepository \
  --configRepoName some-repo-name \
  --configRepoDelete \
  -p <admin-pass> \
  -u <admin-user> \

Create a repository

Hosted Raw
n3dr configRepository \
  --configRepoName some-repo \
  --configRepoType raw \
  -p <admin-pass> \
  -u <admin-user> \
Proxied Apt
n3dr configRepository \
  --configRepoName some-apt-proxy-repo \
  --configRepoType apt \
  --configRepoRecipe proxy \
  --configRepoProxyURL "http://nl.archive.ubuntu.com/ubuntu/" \
  -p <admin-pass> \
  -u <admin-user> \
Proxied Yum
n3dr configRepository \
  --configRepoName some-yum-proxy-repo \
  --configRepoType yum \
  --configRepoRecipe proxy \
  --configRepoProxyURL "http://mirror.centos.org/centos/" \
  -p <admin-pass> \
  -u <admin-user> \

Anonymous access

n3dr config \
  -p <admin-pass> \
  -u <admin-user> \
n3dr config \
  -p <admin-pass> \
  -u <admin-user> \
  -n=<FQDN-without-http://-or-https>:<port-if-applicable> \



docker build -t utrecht/n3dr:6.2.0 .



docker run -it \
  -v /home/${USER}/.n3dr:/root/.n3dr \
  -v /tmp/n3dr:/tmp/n3dr utrecht/n3dr:6.2.0


docker run -it \
  --entrypoint=/bin/ash \
  -v /home/${USER}/.n3dr:/root/.n3dr \
  -v /tmp/n3dr:/tmp/n3dr utrecht/n3dr:6.2.0

navigate to the repository folder, e.g. /tmp/n3dr/download*/ and upload:

n3dr upload -r releases -n <url>

Note: if the snap package is used to upload artifacts, one has to ensure that the folder resides in the /home/$USER folder. Otherwise a: lstat <repository-name>: no such file or directory issue could occur.


One could use --skipErrors or -s to continue-on-error:

n3dr upload -n some-nexus-url \
            -r some-repository \

Store the password in a read-only file

Define the password in ~/.n3dr/config.yml:

n3drPass: admin123

and set the permissions to read-write by issuing:

chmod 0600 ~/.n3dr/config.yml

Note: other variables like n3drURL and n3drUser could also be added to the config file and one could use --config to overwrite the default config path.

Backup artifacts from a certain repository

All artifacts from a repository will be stored in a download folder when the following command is run:

n3dr backup -u admin -n http://localhost:8081 -r maven-releases

Backup artifacts from a repositories list

All artifacts from a repositories list will be stored in a download folder when the following command is run:

n3dr backup -u admin -n http://localhost:8081 -r maven-releases,maven-private

Backup all repositories

All artifacts from various repositories will be stored in a download folder when the following command is issued:

n3dr repositories -u admin -n http://localhost:8081 -b

Note: a new folder will be created for every repository:

Backup only certain artifacts

It is possible to only download artifacts that match a regular expression. If one would like to download all artifacts from ‘some/group42’ then one could do that as follows:

n3dr backup -u admin -n http://localhost:8081 -r maven-releases -x 'some/group42'

If one would like to deploy is while download from all repositories then use the -x option as well:

n3dr repositories -u admin -n http://localhost:8081 -b -x 'some/group42'

Add all downloaded archives to a ZIP archive

In order to add all archives to a zip archive, one has to use the –zip or -z flag.

If one would like to overwrite the default zip file name, then one has to use the -i option. Note: the extension ‘.zip’ is obliged.

Upload all artifacts to a certain repository

It is possible to upload all JARs that reside in a folder by running the following command:

n3dr upload -u admin -n http://localhost:8081 -r maven-public

Upload non maven files

It is possible to upload non maven files like deb files as well by setting the artifactType option to the repository type, e.g. -t=apt. Note that the folder name that contains the files should match the repository name.

“Clone” a Nexus3 repository

Suppose that one has created a new Nexus3 repository, e.g. NexusNEW and that one would like to copy the content of the old repository, e.g. NexusOLD, then these basic steps could be issued to “clone” NexusOLD:

n3dr backup -u <old-nexus3-user> -n <old-nexus3-server-url> \
-r <old-repo-source-name>
cd download
mv <old-repo-source-name> <new-repo-target-name>
n3dr upload -u <new-target-nexus3-user> -n <new-target-nexus3-server-url> \
-r <new-repo-target-name>

Backup to OCI Object Storage

n3dr supports backing up to OCI Object Storage. To enable this option you need to

ociBucket: nexus_dev_archives

If you want to remove local copies (after the object has been uploaded), add following to ~/.n3dr/config.yml:

removeLocalFile: true

Backup NPM repositories

Use the --npm parameter to backup NPM artifacts.

go run main.go backup -npm -n some-url -r some-npm-repo -d --npm
go get -u github.com/gobuffalo/packr/v2/packr2
cd cmd/n3dr
~/go/bin/packr2 clean
mv packrd/packed-packr.go ../../internal/packrd/

Change the main/main-packr.go:

import _ "github.com/030/n3dr/internal/packrd"
go build

Rationale for N3DR

Although there is a number of equivalent tools:

None of them seems to be able to backup all repositories by running a single command.


type backup upload label
apt   x  
maven2 x x +
npm x x *
nuget   x  


type backup upload label
apt x x ^
maven2 x   +
npm x x *
nuget x x $
raw x x %
unknown x x ?


repositoriesV2 command in conjunction with the --backup subcommand ensures that all artifacts are downloaded from Nexus3 and stored in a folder that is defined with the --directory-prefix parameter.

n3dr repositoriesV2 \
  --backup \
  -n some-url \
  -u some-user \
  -p some-pass \
  --directory-prefix /tmp/some-dir


n3dr repositoriesV2 \
  --upload \
  -n some-url \
  -u some-user \
  -p some-pass \
  --directory-prefix /tmp/some-dir


n3dr sync \
  --otherNexus3Passwords=some-pass-B,some-pass-C \
  --otherNexus3Users=admin,admin \
  --otherNexus3URLs=localhost:9998,localhost:9997 \
  --directory-prefix /some/dir \
  -p some-pass-A \
  -n localhost:9999 \
  -u admin

Note: use --https=false in order to connect to a http://nexus-url/.

Stargazers over time

Stargazers over time



Comment out trap in the integration-tests.sh and run it:


Once Nexus had been started, download the go-swagger, swagger.json and generate internal go-swagger code:

export GITHUB_URL=https://github.com
export GS_URI=go-swagger/go-swagger/releases/download
export GS_VERSION=v0.28.0
export GS_URL=${GITHUB_URL}/${GS_URI}/${GS_VERSION}/swagger_linux_amd64
curl -L \
  ${GS_URL} \
  -o swagger
chmod +x swagger
mkdir -p internal/goswagger
curl http://localhost:9999/service/rest/swagger.json -o swagger.json
./swagger generate client \
  --name=nexus3 \
  --spec swagger.json \
  --target=internal/goswagger \
go mod tidy

Unit Tests

go test internal/artifacts/common.go internal/artifacts/common_test.go

Integration testing on Windows


packer init packer/windows2016.json.pkr.hcl
PACKER_LOG=1 packer build packer/windows2016.json.pkr.hcl


vagrant box add virtualbox_windows2016.box --name win2016/n3dr
vagrant box list
vagrant plugin install vagrant-reload vagrant-windows-update
export VAGRANT_N3DR_NETWORK_ADAPTER=$(vboxmanage list bridgedifs |\
  grep Name: | head -1 | awk '{ print $2 }')
vagrant provision nexus3
vagrant destroy -f
vagrant ssh nexus3

Login as vagrant with pass vagrant and issue:

cd C:\vagrant
.\cmd\n3dr\n3dr.exe download -r maven-releases -n \
  -u admin -p some-password
.\cmd\n3dr\n3dr.exe upload -r maven-releases -n \
  -u admin -p some-password

To check whether it is possible to upload artifacts to Nexus3 from Windows using N3DR.