EOS is a software solution that aims to provide fast and reliable multi-PB disk-only storage technology for both LHC and non-LHC use-cases at CERN. The core of the implementation is the XRootD framework which provides feature-rich remote access protocol. The storage system is running on commodity hardware with disks in JBOD configuration. It is written mostly in C/C++, with some of the extra modules in Python. Files can be accessed via native XRootD protocol, a POSIX-like FUSE client or HTTP(S) & WebDav protocol.

The most up to date documentation can be found at: https://eos-docs.web.cern.ch/eos-docs/

You will need to install sphinx, doxygen & solar_theme (for sphinx) in order to generate them. For up to date information on getting sphinx refer to the sphinx docs

## RHEL instructions
# Please choose the revelant python version based on the distro
sudo yum install python-sphinx doxygen
pip install solar_theme

## Ubuntu 20.04 instructions
sudo apt install python3-sphinx doxygen
pip3 install solar_theme

Doxygen documentation of the API is available in the ./doc directory and can be generated using the following command:

# Inside the EOS git clone directory
cd doc
doxygen
....
# Documentation generated in the ./html directory which can be accessed using any browser
# file:https:///eos_git_clone_dir/doc/html/index.html

Sphinx documentation of installation and application is also in the ``./doc'' directory. This is what is published in https://eos-docs.web.cern.ch . Documentation can be generated using the following command:

cd doc
make html
# Documentation can be found in build/html/index.html which can be viewed in a browser
# The make interface can output types as well.

• archive - Archive tool implementation in Python
• auth_plugin - Authorization delegation plugin
• authz - Authorization capability functionality
• client - GRPC clients
• cmake - CMake related scripts and functions
• common - Common helper files and classes
• console - Command line client implementation
• coverage - Test coverage config for LCOV
• doc - Doxygen documentation
• etc - Log rotation files
• fst - The Storage Server Plugin (FST)
• fuse - The FUSE mount Client (eosd low level API)
• fusex- Next generation bi-directional FUSE mount Client with high-end features
• man - Manual pages
• mgm - Meta Data Namespace and Scheduling Redirector Plugin (MGM)
• misc - systemd, sysconfig and service scripts
• mq - Message Queue Server Plugin
• namespace - Namespace Implementation
• nginx - Nginx related patches for EOS integration
• proto - Protobuf definitions for various components
• srm - SRM BestMan utility scripts
• sync - file/directory synchronization programs
• test - Instance test script with some dedicated test executables
• unit_tests - Various unit tests for individual modules
• utils - Useful utilities and the uninstall scripts
• var - Placeholder directory to create log, http and namespace directories

It is recommended to set up xrootd and eos-citrine-dependency repositories, as seen in the documentation.

yum install -y git gcc cmake cmake3 readline readline-devel fuse fuse-devel \
leveldb leveldb-devel binutils-devel zlib zlib-devel zlib-static \
bzip2 bzip2-devel libattr libattr-devel libuuid libuuid-devel \
xfsprogs xfsprogs-devel sparsehash-devel e2fsprogs e2fsprogs-devel \
libmicrohttpd libmicrohttpd-devel openssl openssl-devel openssl-static \
eos-folly eos-rocksdb ncurses ncurses-devel ncurses-static protobuf3-devel \
cppunit-devel openldap-devel hiredis-devel zeromq-devel jsoncpp-devel \
xrootd xrootd-server-devel xrootd-client-devel xrootd-private-devel \
cppzmq-devel libcurl-devel libevent-devel jemalloc jemalloc-devel

To build EOS, you need gcc (>=7) with C++17 features and CMake installed on your system. If you can install ninja, EOS supports ninja for builds.

git submodule update --init --recursive
# Create build workdir
mkdir build-with-ninja
cd build
# Run CMake (pass -DCLIENT=1 if you only need the client binaries)
cmake3 -GNinja ..
# Build
ninja -j 4

Otherwise standard make builds are of course possible

git submodule update --init --recursive
# Create build workdir
mkdir build
cd build
# # Run CMake (pass -DCLIENT=1 if you only need the client binaries)
cmake3 ..
# Build
make -j 4

The default behaviour is to install EOS at system level using CMAKE_INSTALL_PREFIX=/usr. To change the default install prefix path, do the following:

# Modify the default install path
cmake ../ -DCMAKE_INSTALL_PREFIX=/other_path
# if using ninja
ninja install
# Uninstall
ninja uninstall

# Install - might require sudo privileges
make install
# Uninstall
make uninstall

To build the source/binary RPMs run:

# Create source tarball
make dist
# Create Source RPM
make srpm
# Create RPM
make rpm

You can send EOS bug reports to [email protected]. The preferable way, if you have access, is use the online bug tracking system Jira to submit new problem reports or search for existing ones: https://its.cern.ch/jira/browse/EOS

For discussions and help, there is also the eos community which brings together users, developers & collaborators at https://eos-community.web.cern.ch/

EOS - The CERN Disk Storage System
Copyright (C) 2022 CERN/Switzerland This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY, without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.