NERSC partners with ESNet to provide a high speed connection to the outside world. NERSC also provides several tools and systems optimized for data transfer.
External Data Transfer¶
NERSC recommends transferring data to and from NERSC using Globus
Globus is a web-based service that solves many of the challenges encountered moving data between systems. Globus provides the most comprehensive, efficient, and easy to use service for most NERSC users.
However, there are other tools available to transfer data between NERSC and other sites:
- SCP/SFTP: for smaller files (<1GB)
- GridFTP: for large files
Transferring Data Within NERSC¶
"Do you need to transfer at all?" If your data is on NERSC Global File Systems (
/global/cscratch), data transfer may not be necessary because these file systems are mounted on almost all NERSC systems. However, if you are doing a lot of IO with these files, you will benefit from staging them on the most performant file system. Usually that's the local scratch file system or the Burst Buffer.
- Use the the unix command
rsyncto copy files within the same computational system. For large amounts of data use Globus to leverage the automatic retry functionality
Data Transfer Nodes¶
The Data Transfer Nodes (DTNs) are servers dedicated for data transfer based upon the ESnet Science DMZ model. DTNs are tuned to transfer data efficiently, optimized for bandwidth and have direct access to most of the NERSC file systems. These transfer nodes are configured within Globus as managed endpoints available to all NERSC users.