After logging on one of the things that you may wish to do is get data transferred to (or from) the HPC system. Two of the most widely available tools for secure file transfer are SCP (Secure Copy) and SFTP (Secure File Transfer Protocol) which utilize the SSH protocol to implement security. While SCP is a simple, non-interactive command line tool, it is often a more suitable choice when setting up unattended file transfers using scripts. Alternatively, SFTP is an interactive tool which offers features like remote file listing, copying, deleting, directory creation, etc.
While SCP and SFTP are available out of the box on Linux and Mac systems, ITS also offers downloads of Fetch (login required) for MacOS and WS_FTP (login required) for Windows from the Software Download site. In addition, SecureCRT also has SFTP capability. Below are some basic examples showing syntax for both tools. Note that while the examples are specific to Helium, they are broadly applicable, and both commands have extensive man pages available.
Off-campus access to the default ssh/scp/sftp port of 22 has been blocked at the campus border. Therefore, users must specify an alternate port in order for these tools to work from off campus. Helium and Neon use port 40 for off campus, non-VPN access. Some examples below show port specification.
SCP
[user@local ~]$ scp -P 40 file1 hawkid@helium.hpc.uiowa.edu:file1
[user@local~]$ sftp -o port=40 hawkid@helium.hpc.uiowa.eduConnecting to helium.hpc.uiowa.edu...sftp> put file1Uploading file1 to /Users/hawkid/file1file1 100% 840 0.8KB/s 00:00 sftp>
[user@local~]$ sftp hawkid@helium.hpc.uiowa.eduConnecting to helium.hpc.uiowa.edu...sftp> mkdir remotesftp> put local/* remote/Uploading local/file1Uploading local/file2Uploading local/file3sftp> ls remote/remote/file1remote/file2remote/file3
This process is more involved in that one must create the directory remotely first and then transfer the contents from one to the other – wildcards are helpful for this.