Most NERSC login accounts are associated with specific individuals and must not be shared. Sometimes it is advantageous to have a login account which is not tied to a person but instead to the group for the purposes of shared access to batch jobs or data. Collaboration Accounts are designed to facilitate collaborative computing by allowing multiple users to use the same account. All actions performed by the collaboration account are traceable back to the individual who used the collaboration account to perform those actions via gsisshd accounting logs. PIs and PI Proxies can request a collaboration account by submitting a ticket.
Logging Into Collaboration Accounts¶
To access your collaboration account on any Cori login node or on any data transfer node (DTN), use:
$ collabsu <collaboration account name> <enter nersc password at the prompt>
Only your NERSC password is required for collabsu. You do not need your one-time password.
Controlling Collaboration Account Access¶
Each collaboration account has two linux file groups associated with it, one with the same name as the collaboration account and one with the name
c_<collaboration account>. PIs and PI Proxies can give users in their project access to the collaboration account by adding them to the
c_<collaboration account> group in Iris.
External Access and Collaboration Accounts¶
Transferring Data via Globus¶
At the request of the PI or PI Proxy, NERSC can set up a dedicated Globus endpoint that will allow data transfers via Globus as the collaboration account. This is a valuable tool for groups that need to make large data transfers into or out of NERSC and would like the data to be owned by the collaboration account. Only NERSC users who could already become the collaboration account are able to access these endpoints. If you are interested in this, please open a ticket and we'll work with you to set one up.
Access via ssh¶
If you need to have external ssh-based access to NERSC with your collaboration account (for instance for transferring data), you can use sshproxy to generate an ssh key for the account
$ sshproxy.sh -c your_collab_acct Enter the password+OTP for elvis: Successfully obtained ssh key /Users/elvis/.ssh/your_collab_acct Key /Users/elvis/.ssh/your_collab_acct is valid: from 2019-07-16T09:46:00 to 2019-07-17T09:47:58
You can use this key to ssh (or scp, etc.) to any NERSC system.
Collaborative Data Management¶
Large scale experimental and simulation data are typically read or written by multiple collaborators and are kept on disk for long periods. A problem that often arises is that the files are owned by the collaborator who did the work and if that collaborator changes roles the default unix file permissions usually are such that the files cannot be managed (deleted) by other members of the collaboration and system administrators must be contacted. While the problem can be addressed with the appropriate use of unix groups and file permissions in practice this tends to be problematic and a more seamless solution would be of great utility.
Collaborative Software Management¶
The issue with managing software is similar to that of managing data – different collaborators often need to work with the same files in a particular software installation and unix groups and file permissions tend to be problematic for them. The main difference between collaborative data and software management is that software is typically managed on a short-tem basis (hours/days) and smaller in size (~GBs) whereas production data is managed on a long-term basis (months/years) and much larger (~TBs to ~PBs).
Collaborative Job Management¶
Production level jobs are often run by a small team of collaborators. Project accounts would enable members of the team to manipulate jobs submitted by other team members as necessary.