Backing Up Your Data
Backing Up Your Data
The HPC cluster provides the /archive file system for backing up your data.
Transferring your data
You can transfer data two ways. The slow way uses the standard Unix utilities (such as cp, tar, etc) run on the HPC nodes, and is suitable only for small transfers. The fast way uses the Globus service. Globus is about two to five times faster (depending on system traffic), and it should be used for large transfers.
A NOTE ABOUT GLOBUS: We discuss using Globus here specifically to transfer data between the Storrs HPC cluster and /archive storage - but know that Globus does more. Globus comprises large network of endpoints that span the US, and it rapidly transfer data between any two endpoints. The Storrs HPC Cluster and /archive are actually two components of a single such endpoint, which connects the UConn campus.
Preparing Your Data For Transfer
If your data contains many small files (where small means half a megabyte), then you should tar you files up into one or more tarballs and store the tarballs. Although it involves an extra step, this will make faster and easier to transfer you files to
and retrieve your files from /archive, because the system can handle the transfer of large tarballs much
more easily than the transfer of many small files. It also make more efficient use of the /archive file system, owing to the design of the underlying hardware.
Here's an example of using tar.
Suppose your data is in 3 directories. You may find it convenient to create a tarball for each directory, as show in this example
# List directory % ls -l drwxr-xr-x 5 aaa0000 Domain_Users 4096 Jun 22 2018 data1 drwxr-xr-x 5 aaa0000 Domain_Users 4096 Jun 22 2018 data2 drwxr-xr-x 5 aaa0000 Domain_Users 4096 Jun 22 2018 data2
# Make tarballs % tar cf data1.tar data1 % tar cf data2.tar data2 % tar cf data3.tar data3
You can then transfer data1.tar, data2.tar and data3.tar to /archive. To recover your original directories:
# Unpack directories % tar xf data1.tar % tar xf data2.tar % tar xf data3.tar
Moving large files
If your data is mostly in large files (larger than half a megabyte), then you may want to copy your data directly, and not as tarballs.