Setting up to create an experiment page on GMAO Intranet

This page documents the procedure for creating and publishing an experiment on the GMAO Intranet. It is intended as a long-lived reference for GMAO developers running GEOS experiments on NASA HPC systems.

This page describes the steps required to create an experiment on the GMAO Intranet.

Note For clarity, this page refers only to polar, but nearly all steps also apply to train. Any differences will be explicitly noted.

Quick links

• 1. Get an account on polar
• 2. Passwordless SSH (discover → polar)
• 3. CVSACL access on polar
  • Upload SSH key to NCCS
  • Edit ~/.ssh/config
• 4. Create a CVSACL tunnel
• 5. Create an experiment
  • Common makexp errors
• 6. Move plots to polar

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1. Get an account on polar

The first step is to obtain an account on polar.

1. Contact GMAO Support
2. Tell them the account is needed to post experiments on the GMAO Intranet Model Development Page.
3. Ensure you are added to the modeling group.

Once your account is created, verify that you can SSH from discover to polar using your password:

ssh polar

2. Set up passwordless SSH (discover → polar)

To easily move plots from discover to polar, set up passwordless SSH access.

It is assumed that you already have an RSA (or DSA) key on discover.

Check existing SSH keys

On discover, list your public keys:

ls ~/.ssh/*.pub

Example output:

/home/mathomp4/.ssh/id_rsa.pub

Copy your SSH key to polar

Use ssh-copy-id to install the key on polar:

ssh-copy-id -i ~/.ssh/id_rsa.pub polar

You will be prompted for your polar password once.

Verify passwordless access

You should now be able to SSH without a password:

ssh polar

3. Set up CVSACL access on polar

Once logged into polar, you must configure access to CVSACL. This process differs from discover and pleiades.

Upload an SSH key to NCCS

If you have not already done so:

1. Generate an RSA key on polar (if needed).
2. Upload the public key using the NCCS key upload page

See the NCCS QuickStart page for details.

Edit ~/.ssh/config

First, determine your numeric user ID:

id -u

Example:

3456

Edit ~/.ssh/config and add the following entries, replacing 3456 with your UID:

Host cvsacl
    HostName cvsacl.nccs.nasa.gov
    LocalForward 53456 localhost:22223

Host ctunnel
    HostName localhost
    Port 53456

Longer UIDs

If your UID is longer (for example):

31128555

Use the last four digits (8555 in this example). Ports should remain in the 5xxxx range.

Add CVS environment variables

If you use bash, add the following to ~/.bashrc:

export CVS_RSH=ssh
export CVSROOT=:ext:username@ctunnel:/cvsroot/esma

If you use csh or tcsh, add to ~/.cshrc or ~/.tcshrc:

setenv CVS_RSH ssh
setenv CVSROOT :ext:username@ctunnel:/cvsroot/esma

Replace username with your NASA AUID.

4. Create a CVSACL tunnel

Unlike discover or pleiades, polar does not provide an always-on CVSACL tunnel. You must create one manually.

Start a screen session

screen

Connect to CVSACL

ssh cvsacl

You will be prompted for your PASSCODE and password. Once authenticated, the session will appear to hang—this is expected. The connection is holding the tunnel open.

Detach from the screen session using:

Ctrl-a d

You will return to your original shell, with the tunnel still active.

Problems with CVSACL tunnel creation

If you see errors when connecting to CVSACL, you may not have an account.

Contact NCCS Support and ask whether you have CVSACL access, and request account creation if necessary.

5. Create an experiment

Navigate to the experiment directory:

• On polar:

  cd /san_agcm/geos5

• On train:

  cd /gmao/intranet/research/modeling/agcm/geos5

Run the makexp script:

./makexp

You will be prompted for:

• Experiment ID (usually the same as on discover)
• Resolution code (e.g., b72, c48)
• CONTROL expid (baseline experiment, or reuse your expid)
• Description and keywords
• Public or private visibility
• Experiment type (default: climatology)
• Year and season

The experiment will then be checked out from CVS.

Common errors during makexp

Missing CVSACL tunnel

ssh: connect to host localhost port 5xxxx: Connection refused
cvs [checkout aborted]: end of file from server

This means the CVSACL tunnel is not active. Reconnect using screen and ssh cvsacl.

Not in the modeling group

cvs [checkout aborted]: cannot make directory GEOS_Web: Permission denied

You are not a member of the modeling group. See the Get an account section above.

6. Move plots to polar

Navigate to the directory containing your plots on discover. For example:

cd /discover/nobackup/mathomp4/mat-G40B11-c48/plots_CLIM

Run the moveplot script:

$ESMADIR/src/GMAO_Shared/GEOS_Util/plots/moveplot

The first time you run this, you will be prompted for:

• Web server (polar or train)
• Your user ID on that server

This configuration is saved and reused for future runs.

Plots will then be transferred to the intranet experiment directory.