Flexible

EOS is a storage solution for central data recording, analysis and processing++

Adaptable and Scalable

EOS supports thousands of clients with random remote I/O patterns with multi protocol support
WebDAV, CIFS, FUSE, XRootd, GRPC.

Over 930 PB at CERN

Designed for high capacity and low latency.

Security

EOS offers a variety of authentication methods:KRB5, X509, OIDC, shared secret, and JWT and proprietary token authorisation.

Sync & Share

EOS provides Sync&Share functionality for the CERNBox front-end services.

Tape Storage

EOS includes tape storage in combination with the CTA Cern Tape Archive software.

EOS is based on various open source components. The native protocol and framework used for implementation is XRootD. Meta-data is persisted in RocksDB databases using a proprietary KV store called QuarkDB. Data is stored natively in XFS filesystems on hard disks or SSDs or on virtualised back-end storage (e.g. RADOS block devices) or distributed filesystems like Lustre or CephFS.

Namespace / Management Server / MGM

EOS provides a hierarchical namespace. The almost stateless MGM namespace server operates as an active/passive pair in high availabity setups. Meta-data entries for files and directories are cached in the active service component. EOS provides a very flexible access control, quota and access limit system to control the sharing of storage resources within a large user community.

Persistency / QuarkDB

Meta-data is persisted in QuarkDB (a high available KV store backend). QuarkDB uses the RAFT protocol to guarantee persistency in replicated RocksDB databases without downtime. An ideal setup for QuarkDB consists of three linux server with sufficient SSD space.

Storage Server / FST

The data storage server FST provides a plug-in infrastructure for file layouts and storage protocols. The main layouts are replication and erasure encoding of files. While replicated file layouts are ideal for random access, erasure enoded files provide cost-effective storage and high data durability. For file integrity the EOS FST provides optional file and block checksums. The natively supported access protocols of the FST server are XRootD and HTTP(S) based protocols.

Clients / CLI / FUSE

EOS distributes a command line interface for administrative and user commands to interact with the EOS namespace. EOS can be used using a FUSE implementation as a mounted file system on LINUX and Mac OSX based platforms. Windows access can be provided using SAMBA gateways.

DOCUMENTATION

Find the documentation to setup, configure and run EOS

PRESENTATIONS

A collection of presentations about EOS from various conferences

PUBLICATIONS

A collection of published articles about EOS

Next WORKSHOP

Link to register for the next EOS workshop

CERN IT Status Board

Planned Intervations and Incidents

RELEASE NOTES

Release notes of current and previous EOS versions

Workshops