Welcome to CernVM-FS’s documentation!¶
What is CernVM-FS?¶
The CernVM-File System (CernVM-FS) provides a scalable, reliable and low-
maintenance software distribution service. It was developed to assist High
Energy Physics (HEP) collaborations to deploy software on the worldwide-
distributed computing infrastructure used to run data processing applications.
CernVM-FS is implemented as a POSIX read-only file system in user space (a
FUSE module). Files and directories are hosted on standard web servers and
mounted in the universal namespace /cvmfs
. Internally, CernVM-FS uses
content-addressable storage and Merkle trees in order to maintain file data
and meta-data. CernVM-FS uses outgoing HTTP connections only, thereby it
avoids most of the firewall issues of other network file systems. It transfers
data and meta-data on demand and verifies data integrity by cryptographic
hashes.
By means of aggressive caching and reduction of latency, CernVM-FS focuses specifically on the software use case. Software usually comprises many small files that are frequently opened and read as a whole. Furthermore, the software use case includes frequent look-ups for files in multiple directories when search paths are examined.
CernVM-FS is actively used by small and large HEP collaborations. In many cases, it replaces package managers and shared software areas on cluster file systems as means to distribute the software used to process experiment data.
Contents¶
- Release Notes for CernVM-FS 2.5.2
- Release Notes for CernVM-FS 2.5.1
- Release Notes for CernVM-FS 2.5.0
- Overview
- Getting Started
- Client Configuration
- Setting up a Local Squid Proxy
- Creating a Repository (Stratum 0)
- CernVM-FS Server Quick-Start Guide
- Installing the AUFS-enabled Kernel on Scientific Linux 6
- Publishing a new Repository Revision
- Requirements for a new Repository
- Notable CernVM-FS Server Locations and Files
- CernVM-FS Repository Creation and Updating
- Maintaining a CernVM-FS Repository
- Repository Garbage Collection
- Limitations on Repository Content
- Configuration Recommendation by Use Case
- CernVM-FS Server Meta Information
- Setting up a Replica Server (Stratum 1)
- CernVM-FS Repository Gateway and Release Managers
- Advanced Topics
- Appendix
Contact and Authors¶
Visit our website on cernvm.cern.ch.
Authors of this documentation:
- Jakob Blomer
- Predrag Buncic
- Dave Dykstra
- Nikola Hardi
- René Meusel
- José Molina Colmenero
- Radu Popescu