udocker INSTALLATION MANUAL
In most circumstances the end user can download and execute the tool without system administrator intervention. udocker itself is written in Python, but also uses external binaries and libraries to provide a chroot like environment where containers are executed in user space. These tools do not require any privileges.
Python dependencies are described in the file requirements.txt.
udocker requires either pycurl or the curl executable command, to download both the binaries and/or pull containers from repositories.
tar is needed when using
udocker install to unpackage binaries and libraries.
2. USER INSTALLATION
2.1. INSTALL LATEST VERSIONS DIRECTLY FROM GITHUB
Just download and execute the udocker and the installation will be performed automatically.
This installation method contains statically compiled binaries and is built to be used across different hosts and OS distributions.
Once you download the udocker executable from github you can move it around between systems. Once you start it in a new system it will install the required tools. The installation requires outbound network connectivity.
From the master branch:
curl https://raw.githubusercontent.com/indigo-dc/udocker/master/udocker.py > udocker chmod u+rx ./udocker ./udocker install
From the development branch:
curl https://raw.githubusercontent.com/indigo-dc/udocker/devel/udocker.py > udocker chmod u+rx ./udocker ./udocker install
2.2. INSTALL FROM REPOSITORIES
udocker is also available as a tarball in certain repositories such as:
This installation method contains statically compiled binaries and is built to be used across different hosts and OS distributions. Please check the repositories for the latest release.
Install or upgrade of udocker v1.1.2:
curl https://download.ncg.ingrid.pt/webdav/udocker/udocker-1.1.2.tar.gz > udocker-tarball.tgz export UDOCKER_TARBALL=$(pwd)/udocker-tarball.tgz tar xzvf $UDOCKER_TARBALL udocker ./udocker install mv ./udocker $HOME/bin/ # move the executable to your preferred location for binaries
When using the setup.py provided in the release after downloading use:
python setup.py install --home $HOME/bin/
2.3. OBTAINING THE URL OF THE TARBALL
The udocker installation tarball mentioned in section 2.2 can be obtained using the
following method. First download udocker. Second use udocker itself to display the
installation tarball URL by invoking the
version command. The tarball location may
contain several URLs pointing to mirrors.
Then, pick one URL and download the tarball using tools such as curl or wget. By using a previously downloaded tarball and the UDOCKER_TARBALL environment variable as explained in section 2.2, udocker can be deployed without having to downloaded it everytime from the official repositories. The UDOCKER_TARBALL environment variable can also be pointed to an http or https URL.
2.4. FORCE REINSTALLATION
To force download and reinstallation of the udocker tools. Invoke udocker install
with the flag
./udocker install --force
3. SYSTEM INSTALLATION WITH RPMs and DEBs
Beware that these packages contain dynamically linked binaries compiled for the target OS distributions and therefore cannot be execute successfully in hosts running a different OS distribution. To execute the same udocker across systems use the tarball installation methods described above in section 2.
RPMs are provided at http://repo.indigo-datacloud.eu
rpm -i udocker-1.1.X-1.noarch.rpm \ udocker-preng-1.1.X-1.x86_64.rpm \ udocker-freng-1.1.X-1.x86_64.rpm
DEBs are provided at http://repo.indigo-datacloud.eu
dpkg -i udocker_1.1.X-1_all.deb \ udocker-preng_1.1.X-1_amd64.deb \ udocker-freng_1.1.X-1_amd64.deb \ udocker-rceng_1.1.X-1_amd64.deb
Check the INDIGO-DataCloud repository for the latest versions and supported distributions.
X in the examples with the latest version.
Notice that the rc engine (udocker-rceng) package is only available for Ubuntu 16 and 18.
4. SYSTEM INSTALLATION WITH ANSIBLE AND PYTHON
For system administrators wishing to provider udocker and its dependencies, an ansible playbook is provided in the file ansible_install.yaml:
curl https://raw.githubusercontent.com/indigo-dc/udocker/master/ansible_install.yaml > ansible_install.yaml ansible-playbook ansible_install.yaml
Under debian based systems ansible can be installed with:
apt install ansible
Under RH based systems ansible can be installed with:
yum install epel-release yum install ansible
Optionally installation can be performed directly with pip:
pip install git+https://github.com/indigo-dc/udocker
5. SOURCE CODE
To get the master branch:
git clone https://github.com/indigo-dc/udocker
To get the latest udocker script from the github devel branch without cloning the entire repository. This downloads udocker.py only.
To get the udocker source code repository from the github master branch, clone the
repository, or use a web browser to access github at
git clone https://github.com/indigo-dc/udocker
To get the udocker source code repository from the devel branch.
git clone https://github.com/indigo-dc/udocker cd udocker checkout devel
A distribution tarball can be built using the script build_tarball.sh in the utils directory. The script fetches the code necessary to build the binary executables such as proot and compiles them statically. The following example builds the tarball from the master repository.
git clone https://github.com/indigo-dc/udocker cd udocker/utils ./build_tarball.sh
The binary executables and containers are usually kept in the user home directory under $HOME/.udocker this directory will contain:
- Additional tools and modules for udocker such as proot.
- Data from pulled container images (layers and metadata).
- Directory trees for the containers extracted from the layers.
The location of the udocker directories can be changed via environment variables.
- UDOCKER_DIR : root directory of udocker usually $HOME/.udocker
- UDOCKER_BIN : location of udocker related executables
- UDOCKER_LIB : location of udocker related libraries
- UDOCKER_CONTAINERS : location of container directory trees (not images)
- UDOCKER_KEYSTORE : location of keystore for repository login/logout
- UDOCKER_TMP : location of temporary directory
- UDOCKER_TARBALL : location of installation tarball (file of URL)
- UDOCKER_NOSYSCONF: do not read system wide config files in /etc
The Docker index and registry and be overrided via environment variables.
- UDOCKER_INDEX : https://...
- UDOCKER_REGISTRY : https://...
The verbosity level of udocker can be enforced. Removing banners and most messages can be achieved by executing with UDOCKER_LOGLEVEL=2
- UDOCKER_LOGLEVEL : set verbosity level from 0 to 5 (MIN to MAX verbosity)
Forces the use of a curl executable instead of pycurl and enables selection of a given curl executable pathname:
- UDOCKER_USE_CURL_EXECUTABLE : pathname to the location of curl executable
udocker loads the following configuration files:
- $HOME/.udocker/udocker.conf (if different from the above)
The configuration files allow modification of the udocker Config class attributes. Example of the udocker.conf syntax:
dockerio_registry_url = "https://myregistry.mydomain:5000" http_insecure = True verbose_level = 5