CVMFS < IT < TWiki

---+ CVMFS at Glasgow

CVMFS is a network file system based on HTTP and optimized to deliver experiment software in a fast, scalable, and reliable way. It was originally developed as part of the [[http://cernvm.cern.ch/portal/][CernVM]] project and has the following features: 

   * Caching, Read-only
   * Based on very standard technologies - outgoing http, fuse...
   * Scales very easily with additional squid caches
   * File checksums (currently SHA1) are verified against a trusted catalog obtained over HTTPS
   * File based deduplication as a handy side effect of the signed file catalog
   * Uses fuse to mount a virtual filesystem (based on a signed-catalog downloaded form the server)
   * Performance is close to a locally installed sofwtare after initial cache population
   * Jobs run faster than with either NFS or AFS
   * Removes the need for local software install jobs at every site

(borrowed from the gridpp CVMFS page [[https://www.gridpp.ac.uk/wiki/RAL_Tier1_CVMFS]])

---+++ CVMFS on batch and desktops

The CVMFS repositories are mounted under the <code>/cvmfs</code> directory. Currently the <code>ams.cern.ch</code>, <code>atlas.cern.ch, <code>atlas-condb.cern.ch</code>, <code>atlas-nightlies.cern.ch</code>, <code>cms.cern.ch</code>, <code>geant4.cern.ch</code>, <code>lhcb.cern.ch</code>, <code>na61.cern.ch</code> and <code>sft.cern.ch</code> are repositories are available.

<verbatim>
[~]$ ll /cvmfs
total 5
dr-xr-xr-x 2 root  root     0 Nov  8 13:28 ams.cern.ch
drwxrwxr-x 1 cvmfs cvmfs    0 Mar  5  2012 atlas.cern.ch
drwxr-xr-x 2 cvmfs cvmfs    0 Nov  8 13:28 atlas-condb.cern.ch
drwxr-xr-x 2 cvmfs cvmfs    0 Nov  8 13:28 atlas-nightlies.cern.ch
dr-xr-xr-x 2 root  root     0 Nov  8 13:28 cms.cern.ch
drwxr-xr-x 2 cvmfs cvmfs    0 Nov  8 13:28 geant4.cern.ch
dr-xr-xr-x 2 root  root     0 Nov  8 13:28 lhcb.cern.ch
dr-xr-xr-x 2 root  root     0 Nov  8 13:28 na61.cern.ch
dr-xr-xr-x 2 root  root     0 Nov  8 13:28 sft.cern.ch
</verbatim>




-- Main.AndrewPickford - 2013-11-11
This topic: IT > WebHome > CVMFS
Topic revision: r1 - 2013-11-11 - AndrewPickford