Connect & Login
SSH (and scp) access to the BG/P systems requires SSH keys or a one-time password generated by a CRYPTOCard token.
- Surveyor.alcf.anl.gov (cryptocard or ssh key)
- Intrepid.alcf.anl.gov (cryptocard only)
Once you have an account and have set up your SSH keys and/or CRYPTOCard token, you may log onto the BG/P systems. Use the following login hosts: surveyor.alcf.anl.gov intrepid.alcf.anl.gov. The login hostnames refer to all currently available user login hosts. Users are placed onto the real hosts in round-robin fashion. As a result, they may end up on a different host from one login to the next. Because the real hosts may change without notice, we suggest that you use the alias and not the real hostnames to log onto the system.
Using SSH on the ALCF BG/P Surveyor System
Accessing the ALCF BG/P system Surveyor via SSH can be done with any SSH software package. Before logging in, you will need to generate an SSH public key and send it to support@alcf.anl.gov for verification and installation.
Generating a Key
If you have not yet generated an SSH key, you can do so by running:
ssh-keygen -t rsa -b 2048
Input a secure passphrase that you don't use anywhere else when requested, and then send the
~/.ssh/id_rsa.pub
file that is created afterward to support@alcf.anl.gov with the request to have it added to your account.
If you already have an SSH key, just send the public key part to the above address.
NOTE: Do NOT send id_rsa to us, only id_rsa.pub.
Logging In
To log in to Surveyor from a Unix machine, ssh to surveyor.alcf.anl.gov:
ssh surveyor.alcf.anl.gov
If your username on your local machine is different from your username on Surveyor, you will need specify your ALCF account username within the SSH command. This can be done two ways: by using the -l option or by prepending your username to the hostname.
ssh -l alcf_username surveyor.alcf.anl.gov ssh alcf_username@surveyor.alcf.anl.gov
Once you have connected, you will be prompted for your SSH passphrase. "Accessed Denied" error messages at login usually mean there is a passphrase or username problem. If you are experiencing this problem, use the -vv option to ssh (or scp) to get diagnostic output and send that output, along with your username on both systems, to the ALCF help desk.
Copying Files
Copying files to and from Surveyor can be accomplished with the scp command. The format of the scp command is very similar to the format of using ssh:
scp localfile surveyor.alcf.anl.gov:/path/to/remote/file
If you wish to copy an entire directory, use the -r option:
scp -r localdir surveyor.alcf.anl.gov:path-to-remotedir
Once again, if your local username differs from your ALCF account username, you will need to specify the ALCF account username within the scp command. The -l option will not work, so you must prepend the username:
scp localfile alcf_username@surveyor.alcf.anl.gov:path-to-remotefile
The method used to copy files to and from Surveyor may need to take into account any firewalls between your local machine and Surveyor. It is possible that there is a firewall that will prevent access to your local machine from the Argonne LCF BG/P network. This can make copying files from Surveyor to your local machine seem difficult. If you are logged onto one of the front-ends and you are unable to scp files to your local machine using the standard scp format, try pulling the Surveyor files using scp on your local machine:
scp surveyor.alcf.anl.gov:path-to-remotefile localfile
Notice that you are simply swapping the local and remote filenames. The prepending of the username and use of the -r option will work with this format as well.
Extra Information
The surveyor.alcf.anl.gov name refers to all currently available user login hosts. Users are placed onto the real hosts in round-robin fashion. As a result you may end up on a different host from one login to the next. Because the real hosts may change without notice, we suggest that you use the alias and not the real hostnames to log onto the cluster.
For more information on using ssh and how to obtain a version for your local machine, please read the MCS Offsite Access document. This document also contains information on why ssh is necessary and pointers to other useful sources of information on ssh and scp.