Multiple Computing Groups
With the new Account Management launched in November and the associated move of Computing Groups from CRA to the E-Groups application,
it is now possible for an account to be a member of multiple computing groups.
Note that the user has one primary computing group and optionally, multiple secondary computing groups.
Having a single account in multiple Computing Groups is attractive for people working for multiple collaborations.
They will have a single AFS Home Directory to store their files, but will be able to get access to the resources
(files, LSF slots) of the collaborations they work for. This reduces the need for separate accounts.
Default Computing Group
A new Computing Group, with self-service subscription enabled has been created:
def-cg
This is the default Computing Group to which any user can subscribe, when going to
the Account Management Portal http://www.cern.ch/account ->
Services -> Linux and AFS -> Subscribe.
Subscribing to this Computing Group automatically enables Linux and AFS service access.
If you need to join another Computing Group, there is no need to unsubscribe from this default group def-cg, simply follow the
procedure below to change your primary computing group.
If you still wish to be removed for any reason, please go to http://e-groups.cern.ch -> Show all groups i'm on
and click the "Unsubscribe" button on the def-cg group.
Multiple Computing Groups
Using the E-Groups application or contacting their Computing Group Administrators,
users can be member of several different Computing Groups.
On the AFS side, there is no Primary Group concept, but in LXPLUS, the Primary Group predefines the environment that will be loaded.
Depending on the tasks you wish to perform, you may need to have a specific primary group and environment
(such as experiment specific PATH) to work.
Permanent Primary Computing Group change
Changing your primary computing group permanently can be performed by the user.
This is used when the main responsibility of the user has changed, such as moving to a new experiment where
the majority of work will be performed. The old primary computing group remains available for occasional use.
You can change your primary computing group selecting the LXPLUS and Linux service in the Resources Portal
http://www.cern.ch/resources.
Please note that it takes several minutes for this change to be propagated to the central Linux clusters such as LXPLUS.
On machines with 'locally' managed accounts, use the 'usermod' command to achieve this.
Using groups with lxbatch
The CERN LSF facility used by lxbatch allows the use of primary and secondary groups.
When you use the procedure above to temporarily set your primary group,
any LSF jobs submitted will use the temporary group for the job priority in the queue, environment when executing and accounting.