BGV Project Folder on AFS

The BGV AFS folder has been removed due to the AFS Phaseout.
EOS is used instead.
The afs group "bgvsa:afsuser" was deleted, as well as the service account "bgvsa"
The info on this page is outdated.

Overview

A dedicated BGV project folder is available on the CERN AFS: /afs/cern.ch/project/lhcbgv

The functioning of this afs folder is like any CERN afs folder. The info on this page is relevant to the administration of the project folder (management of volumes, quotas and ACLs). In practice, this involves the management of:

  • User access rights
  • The top-level folder structure

The info here follows the description given on the CERN IT webpage: http://information-technology.web.cern.ch/book/afs-administrator-guide

Management of the user access rights

Like any AFS folder, the access rights of the BGV project folder are managed with "access control lists" (ACLs). For a description, see this page: http://information-technology.web.cern.ch/services/fe/afs/howto/configure-afs-access-rights. The current baseline configuration (June 2015) is the following:

AFS user or group Access rights Description
system:anyuser rl Any CERN AFS user. This ACL was added in order to provide read rights to everybody with access to AFS
_lhcbgv_ rlidwka Administrator group of the BGV project space
system:administrators rlidwka CERN AFS admin group

The table above shows the baseline setting for all files and folders in the BGV project space. In addition, the following rights are provided:

Folder AFS user or group Access rights Description
user/<user> <user> rlidwk Write rights for a user in his/her dedicated folder
L0Trig qveyrat rlidwk Write rights for Quentin in the L0Trig folder

A dedicated AFS group called bgvsa:afsuser was created to facilitate the management of ACLs in the BGV project space. Currently (June 2015) it is not used, but can be employed e.g. in a scenario where one wants to provide write rights to a given folder. Instead of setting the ACL for each user separately, one can just set the ACL for the bgvsa:afsuser group. In this case one needs to manage (add/remove) the members of the group. This AFS group is owned and can be managed by the BGV service account bgvsa (currently assigned to Plamen). Details about the management of AFS groups can be found on the IT webpage: http://information-technology.web.cern.ch/services/fe/afs/howto/work-afs-groups

To check the members of an AFS group: pts membership -nameorid bgvsa:afsuser

Management of the top-level folder structure

To allocate disk space to a certain afs folder, an "AFS volume" must be created and space quota to be defined. A description provided by IT (J. Iven):
One concept that you should quickly look into is the creation of AFS volumes (which correspond to subdirectories within your project) - the volume quota on the top-level volume p.lhc_bgv.root == /afs/.cern.ch/project/lhc_bgv is deliberately small, in order for you to create new volumes underneath.. many small volumes are better than a single large one, and together will allow you to use more than 100GB. (This is the "practical implication" - a single volume is a subtree in AFS, sits on a single RAID1, and the size of it is constrained. Small volumes make our life easier (backups, moves), and spread load from your clients over several AFS servers).

The initial total quota is 150 GB. In case of need, increase is possible.

The standard operations and commands are described here: http://information-technology.web.cern.ch/book/afs-administrator-guide

Edit | Attach | Watch | Print version | History: r4 < r3 < r2 < r1 | Backlinks | Raw View | WYSIWYG | More topic actions
Topic revision: r4 - 2019-08-26 - PlamenHopchev
 
    • Cern Search Icon Cern Search
    • TWiki Search Icon TWiki Search
    • Google Search Icon Google Search

    BGV All webs login

This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2023 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
or Ideas, requests, problems regarding TWiki? use Discourse or Send feedback