As of February 26, 2014 the AuN/Mc2 file system is mounted on BlueM. Thus to move a file to/from AuN or Mc2 the transfer can be done directly to/from BlueM. This reduces the importance of setting up tunnels to do transfers. However, tunneling, as discussed here, can still be useful for copies and login sessions.

See: http://hpc.mines.edu/bluem/mounted.html for information about accessing AuN and Mc2 files from BlueM.

This document discusses:

The file system on Aun and Mc2 and BlueM

At first login on you have some directories set up for you

The subdirectories under the "remote" directory on bluem are links to directories on AuN and Mc2 as shown below. Read/writes in these directories are actually read/writes to AuN and Mc2. Thus the easiest way to get data to/from AuN or Mc2 might be to access the files from bluem.

bluem:remote/aun/home
AuN:home
bluem:remote/aun/scratch
scratch
bluem:remote/aun/bins
AuN:bins
bluem:remote/mc2/home
Mc2:home
bluem:remote/mc2/scratch
scratch
bluem:remote/mc2/bins
Mc2:bins

Aun and Mc2 share a common file system. Files written to your scratch directory on either machine are visible on the other.Your scratch directory should be used for the output of parallel applications, not your home directory. Side note: The minimum files size on scratch in 4Mbytes. That is if you have a file of size less that 4Mbytes it still occupies 4Mbytes on disk. Thus, users should avoid small files by using the tar or zip command to combine small files into a single file.

Aun and Mc2 have their own home directories but it is possible to "see" the home directory on the other machine.

Aun and Mc2 each have a separate bins directory. The bins directory is where you should keep applications that you build. Again, it is possible to "see" the bins directory on the other machine.

Using scp with tunnels

Scp is the normal way to transfer files between machines. Transfers must occur through BlueM. Since BlueM now has links to the file system of AuN and Mc2 you can now copy data directly to/from BlueM.<

However, there is a method called tunneling that users can set up that allows (what appears to be direct) connection to AuN and Mc2. This can be use for both file transfers and logins. A copy/paste guide for setting up tunneling is available at:
http://hpc.mines.edu/access

After a tunnel is set up it appears to scp that there is a direct connection between the machines. Essentially, there is alias set up for the remote machine. Transfers to the alias go to the remote machine by way of the intermediate, BlueM in this case. The procesure discussed at http://hpc.mines.edu/access sets up the aliases:

golden
aun
energy
mc2
golden2
aun
energy2
mc2

What this says is that if you reference "golden" as a remote host for an scp command the traffic will be routed to aun.mines.edu by going through bluem.mines.edu and traffic directed to energy will go to mc2.mines.edu via bluem.

They syntax for scp is a bit demanding. In its full form you must specify the source/destination in the form:

scp source_username@source_host:source_directory destination_username@destination_host:destination_directory

Usually, you can shorten the source designation to the path to the file(s) that are being moved.

There is command available on the various machines, /opt/utility/scpath. Run in a directory, it provides the fully qualified local path for scp. If you add file(s) to the command it gives the path for the file(s). For example on Aun we can get:

[joeuser@aun001 ~]$ /opt/utility/scpath
joeuser@aun001.mines.edu:/u/pa/ru/joeuser
[joeuser@aun001 ~]$ 
[joeuser@aun001 ~]$ /opt/utility/scpath *f90
joeuser@aun001.mines.edu:/u/pa/ru/joeuser/int_sin.f90
joeuser@aun001.mines.edu:/u/pa/ru/joeuser/mult.f90
joeuser@aun001.mines.edu:/u/pa/ru/joeuser/pointerc.f90
joeuser@aun001.mines.edu:/u/pa/ru/joeuser/test2.f90
joeuser@aun001.mines.edu:/u/pa/ru/joeuser/tio.f90
[joeuser@aun001 ~]$ 

We note that the machine name is aun001.mines.edu. If we want to use the tunnel alias this should be changed to golden. If the command is run as tcpath this is done automatically. For example:

[joeuser@aun001 ~]$ /opt/utility/tcpath
joeuser@golden:/u/pa/ru/joeuser
[joeuser@aun001 ~]$ /opt/utility/tcpath *f90
joeuser@golden:/u/pa/ru/joeuser/int_sin.f90
joeuser@golden:/u/pa/ru/joeuser/mult.f90
joeuser@golden:/u/pa/ru/joeuser/pointerc.f90
joeuser@golden:/u/pa/ru/joeuser/test2.f90
joeuser@golden:/u/pa/ru/joeuser/tio.f90
[joeuser@aun001 ~]$ 

Example usage of scp with tunneling

We assume that we have set up a tunnel on RA to Aun/Mc2 by running the command /opt/utility/settunnel. We want to transfer some *f90 files from RA to Aun.

On Aun

[joeuser@aun001 optic]$ /opt/utility/tcpath
joeuser@golden:/u/pa/ru/joeuser/scratch/optic

We copy the string returned by this command so that we can paste it on RA.

On RA:

[joeuser@ra5 split]$ scp  S*f90 joeuser@golden:/u/pa/ru/joeuser/scratch/optic 
SEARCH.f90                               100%  318     0.3KB/s   00:00    
SIGBM.f90                                100%  643     0.6KB/s   00:00    
SIMPSN.f90                               100%  402     0.4KB/s   00:00    
SLOPEI.f90                               100% 1781     1.7KB/s   00:00    
SP.f90                                   100% 1234     1.2KB/s   00:00    
SPL.f90                                  100% 1191     1.2KB/s   00:00    
SPLINE.f90                               100% 1109     1.1KB/s   00:00    
SPLIN.f90                                100% 1164     1.1KB/s   00:00    
Killed by signal 1.
[joeuser@ra5 split]$ 

The Killed by signal 1. is normal indicating that the tunnel has shut down.