Data Management and Transfers on The NFS Disk

As mentioned in the Scratch Disk section, when causing network traffic to the NFS disk, it will slow down processes on Elja, resulting in sluggish behavior for all other Elja users working in their home directories. If you need to transfer data to or from the NFS disk, it is required to set the bandwidth to a maximum of 40000 Kbit/s (5 Megabytes). If users do not set the bandwidth in that range, the system administrators will shut down the process and notify the individual.

Below are different methods on how to apply bandwidth restriction to rsync and scp.

rsync

To restrict the bandwidth when using rsync, you will need to add the parameter --bwlimit=40000 like the following:

$ rsync -av --bwlimit=40000 -e "ssh -i /path/to/your/ssh/keyfile" <uname>@elja.hi.is:/users/home/<uname>/../data /path/on/local/computer/ # -av Archive mode with verbose input

This command shows an example for a user who is transferring data located in the user's home directory on Elja to the location "/path/on/local/computer" on the local computer.

scp

To restrict the bandwidth when using scp, you will need to add the parameter -l 40000. An example of such a case is displayed below:

$ scp -l 40000 -p -r <uname>@elja.hi.is:/hpcapps/users/home/<uname>/ .

Here we are transferring data located in a user's home directory on Elja to the current location on the local machine that the user is working in.