Using bbcp at NERSC¶
Bbcp is a point-to-point network file copy application with excellent network transfer rates. The application was originally written for transferring large files of the data-intensive High-Energy Physics community. Bbcp is available on the NERSC Data Transfer Nodes.
To transfer files into/out of NERSC using bbcp, you need an SSH client. For most Unix-like systems (Linux//MacOS/Cygwin), the command ssh is sufficient and the bbcp executable. You can download the bbcp executable from the maintainer's site.
All example commands below are executed on your local machine, not the NERSC machine:
The syntax of bbcp is similar to the syntax of scp, with some special options specifying how to run ssh/bbcp.
Get a file from Data Transfer Node:
bbcp -S "ssh -x -a -oFallBackToRsh=no %I -l %U %H /usr/common/usg/bin/bbcp" "firstname.lastname@example.org:/remote/path/file" /local/path
Send a file to Data Transfer Node:
bbcp -T "ssh -x -a -oFallBackToRsh=no %I -l %U %H /usr/common/usg/bin/bbcp" /local/path/file "email@example.com:/remote/path/"
Get a file from an outside host to NERSC:
bbcp -S "ssh -x -a -oFallBackToRsh=no %I -l %U %H /path/to/bbcp/on/remote/host" "firstname.lastname@example.org:/remote/path/file" /local/path
Send a file from NERSC to an outside host:
bbcp -T "ssh -x -a -oFallBackToRsh=no %I -l %U %H /path/to/bbcp/on/remote/host" /local/path/file "email@example.com:/remote/path/"
Note the difference between "-S" and "-T" option, "-S" means the source (where the data come from), "-T" means the target (where the data goes to).
In case you get the following error or similar, add the "-z" option to your command line (right after bbcp).
bbcp: Accept timed out on port 5031 bbcp: Unable to allocate more than 0 of 8 data streams. Killed by signal 15.