First Steps


Before starting to work on your analysis (this means for example using the computing system and internal web pages) you first need to do more or less technical things. Within this page we give a step-by-step explanation to the very beginners. To follow the instructions below you DO NOT NEED to be at Fermilab in person (see topic Coming to Fermilab). 
In Section 1 you will learn how to get the basic accounts and the very important Fermilab Visitor ID. After obtaining the accounts, Section 2 explains to you how to login correctly and what to do first. When you have passed Section 3 (example for setting up a DØ environment) you can start with your analysis ! 


Section 1 - Accounts, Registration

This section gives you an outline for getting accounts. Detailed information can be found at:

DØ mainpage => DØ at work => Compting & Core Software => Computer Accounts

Most of the forms and a lot of other information can be found on the
Fermilab International Services web page as well. 
In particular follow the link to the Users' Office.

The most important (and inevitable) thing is to get a Fermilab Visitor ID. This is MANDATORY - even if you will never appear in person at Fermilab:

(1)  Go to Fermilab Visitor ID verification.
(2)  An important part of this verification is that you read and attest by signature that you have read the Fermilab Policy on Computing.

OFF-SITE USERS (Non-Fermilab-Employees): 
(3)  Go to Application to Use Fermilab Computers from Off-Site (for Non-Fermilab-Employees).

(3)  Follow the instructions on this page (print out and fill out application).
(4)  Obtain a signature from A. Jonckheere or one of the spokespersons.
(5)  Take the form to the User's Office in WH (= Wilson Hall, see map). 

Some remarks (thanks to A. Jonckheere):
The time period before expiration of a Fermilab ID is complicated.
There are two parts to it: ID authorization and the physical ID itself.
People who have never been here will only have an authorization.

The ID authorization will be valid for either 1 or 3 years depending on your
work status. A student's, including a post doc's, authorization will expire in 1 year.
A person with a 'permanent' job (professor at any level, engineer etc)
will have an authorization that will expire in 3 years.

The physical ID will expire at the earlier of a number of things, visa
expiration and ID authorization expiration are the most important.
But, again, you don't need a valid physical ID unless you are here on-site.

Before the ID expires you will receive an expiration notification.
For renewing your ID please use the form at:

DØ mainpage => DØ at work => Compting & Core Software => Computer Accounts => Obtain or Renew Visitor's ID and Kerberos Account.

This form can also be used if the ID has expired.

Further reading:
Overview from Fermilab Computing Division:
Fermilab mainpage => Fermilab at work => Fermilab Divisions and Sections => Computing Division  => Services  

When you have got your ID (after a few days), you can start the procedure for getting DØ accounts

(1)  Go to DØ Accounts Request Form and read carefully the NOTICE TO USERS. 
(2)  If you accept the rules, click on continue. The following page just reminds you that you can only continue with a valid ID - click again on continue.
(3)  Fill in and submit the form.

Some Remarks:
-  Your username is limited to 8 characters. Keep in mind, that all accounts - including your email - will use this username.
-  Check the box 'IMAP Account' to get an FNAL email address.
-  In order to work on DØ machines, you have to check the boxes 'D0 Central Analysis Systems' and 'Clued0 desktops' in the section 'D0 Unix'.  A working directory will be created for you; login name: 'username'. In order to be able to see all DØ web pages you need also to check the box 'D0Web'.
-  In order to access the DØ Wiki pages please contact Gustaaf Brooijmans ( He will validate your wiki account. 

Further reading:
DØ Computing Systems and Operations (overview): 
DØ mainpage => DØ at work => Computing & Core Software => DØ Computing Systems.
ClueD0: DØ mainpage => DØ at work => Computing & Core Software => Clued0.
Accounts and Passwords overview from Fermilab Computing Division:
Fermilab mainpage => Fermilab at work => Fermilab Divisions and Sections => Computing Division => Services => Getting Services => Accounts and Passwords.
Kerberos in detail: 
Fermilab mainpage
=> Fermilab at work => Fermilab Divisions and Sections => Computing Division => Services => Getting Services => Kerberos.

Now you have to change the initial passwords which you receive per email (except for Kerberos password, see Section 2).

(1)  Change web password
(2)  Change email password and check email forwarding (e.g. forward to username@home_institute.domain). 

During your analysis you will be able to use the data handling system SAM (= Sequential data Access via Meta-data). This requires a one-time registration, which can easily be done via the SAM Auto Registration Form. Just fill in the boxes and click on 'Register/Update'. This form can also be used to modify your account (e.g. changing/adding the working group entries).

Getting DØ software packages from the CVS (= Concurrent Version System) repository (i.e. to run '> addpkg <pkg>' or '> cvs co <pkg>') needs a separate registration only if you did not check the box 'D0 Central Analysis Systems' in the DØ Account Request Form. The registration can be done by sending an email to This mail should contain your kerberos principal ('') and a short comment ('Please register me to use the d0cvs repository.'). You can also use this email address to report CVS related problems. 

Further information:
DØ mainpage => DØ at work => Computing & Core Software =>  Infrastructure => Software Tools => Code Management => Howto => Can't access d0cvs.

You may optional get an IMAP account. Please note that having a Fermilab email address ( does NOT mean to have a Fermilab email account. You have to check the corresponding box in the DØ Account Request Form.

Please have a look at Email at Fermilab web pages for further information about using IMAP, Servers, FAQ, . . . : 
Fermilab mainpage
=> Fermilab at work => Fermilab Divisions and Sections => Computing Division => Services => Getting Services =>  Email.

Don't forget to change the email forwarding (e.g. forward to

Direct link to to web interface: Fermilab Webmail.


Section 2 - First Login

Be aware of the Strong Authentication at Fermilab !

  Actions which constitute blatant disregard for Laboratory computer security  

Before going on you should have
- a valid Fermilab ID
- a Cryptocard
- an initial Kerberos password
- an initial PIN for your Cryptocard (if you checked the corresponding box in the DØ Account Request Form)

First follow the instructions delivered with your Cryptocard concerning PIN (enter the initial PIN and then change it).

Login on a Clued0 machine (from outside Fermilab, with Cryptocard):

your_desktop_at_home>  ssh -X -l username

     username: The username you have selected in the DØ Accounts Request form.
     login_machine: A computer hosted by your group.

Now try to login on a selected machine (ask your group members to find out which machines you own). On your desktop might appear something like this:

> ssh -X -l magass
> The authenticity of host ' (' can't be stablished.
> RSA key fingerprint is a1:b2:c3:d4:e5:f6:g7:h8:i9.
> Are you sure you want to  continue connecting (yes/no)? [e.g. type 'yes']
> Warning : Permanently added ' (' (RSA) to the list of known hosts.
> Press ENTER and compare this challenge to the one on your display: 12345678 [for example]
> Enter the displayed response: 

Once only the Cryptocard has to be synchronized. Follow the instructions delivered with your Cryptocard (press 'MENU', enter PIN, enter the challenge displayed [here: 12345678]). Then a password will appear (e.g. R43THL82). You need to enter this password on your PC - and you're in ! 

The next time you login, you DO NOT NEED to repeat the synchronization procedure. Just take your Cryptocard, press 'PASSWORD', enter PIN and then enter the displayed password on your PC - and you're in !

Login on a Clued0 machine (from outside Fermilab, without Cryptocard):

This is only possible, if your computer system supports Kerberos. 

your_desktop_at_home>  kinit username@FNAL.GOV 
Password for username @ FNAL.GOV:  [enter your Kerberos Password]
your_desktop_at_home>  ssh -X -l username

In this case you will not again be asked to enter code generated with your Cryptocard.

Login on a Clued0 machine (inside Fermilab):

Simply enter username and Kerberos password.

The first thing is - however you logged in - to change your initial Kerberos password via 'kpasswd':     
> kpasswd
> kpasswd: Changing password for username
> Old password:
At first enter the old password. Then you will be asked to enter new password (twice). 
> New password:
> New passwork (again):
> Kerberos password changed.

Setting up your home area:

Your clued0 home area is on the d02ka home disk. It is the subdirectory in your home area called 'desktop'. Please check that this directory exists and has the correct user access permissions set (+rwx). This can be accomplished by logging in to your d0mino (d0min01, d0mino02 or d0mino03) home area and typing:
>  ls -ld desktop 

If this directory does not exist (or does not have sufficient access priveleges) you will need to create it:
mkdir desktop
chmod 755 desktop

Some important guidelines:

We impose quotas of 250Mb on home areas of new users. This space is backed-up nightly. You may request more space if you need it. Please put big files on your local disks.
Questions about the cluster should be sent to
We run batch queues on all machines in the cluster. If you have a long job (> 1 hour) to submit please use these queues. Running interactively will interfere with others submitting batch jobs to the queues. The batch system will submit your job to the fastest, least used machine in the is to your advantage to use the batch system.

Further reading:

Getting started with Computing at Fermilab:
Fermilab mainpage => Fermilab at work => Fermilab Divisions and Sections => Computing Division => Services => Getting Started
Instructions on batch usage:
DØ mainpage => DØ at work => Computing & Core Software => ClueD0  => Info for Users => The Batch System => Instructions.


Section 3 - Setting up an environment

  How To Use The DØ Software Releases  

(1)  Login as written in Section 2.
(2)  Due to restricted disk space in home areas, create a working area on a machine owned/maintained by your home institute. If you want to use another institutes disk space you have to ask for permission first. Please have a look at ClueD0 Disk Policies on Clued0 Homepage or contact
e.g. user 'magass', member of group 'german', institute 'aachen' => aragorn-clued0, arwen-clued0, galadriel-clued0

cd /work/galadriel-clued0
mkdir magass
cd magass

(3)  Standard setup sequence (here for production version p21.10.00, see DØ Software Releases):

setup D0RunII p21.10.00 -O SRT_QUAL=maxopt
setup sam
setup d0cvs
setup d0tools

With the 'ups' command you can check the availability of existing versions:

setup ups
ups list -aK+ D0RunII
ups list -aK+ root    . . .

(4)  Creating a new release area with 'newrel'

newrel p21.10.00 my_analyze
>  Creating a test release "my_analyze" in the directory
>         /work/galadriel-clued0/magass
cd my_analyze
d0setwa   ( = set working area)

Don't forget the standard setup sequence (and d0setwa) after logging in anew !

(5)  In this directory you can now add packages from the CVS repository (after registration, see above), write and compile your code. As an example we checkout the package tmb_analyze from the release p21.10.00. 

addpkg tmb_analyze
Release p21.10.00 uses tmb_analyze version p21-br-10, will check that out 
Adding package "tmb_analyze" to ".". 
using package special cvs server cvs -d checkout -P-r p21-br-10 tmb_analyze 
cvs checkout: Updating tmb_analyze 
U tmb_analyze/GNUmakefile U tmb_analyze/LIBDEPS 
 [ ....]
 [this may take a while ....]

If you want to see all options provided for checking out packages just enter 'addpkg'.

Wiki Starting With The D0 Framework Today 

If something doesn't work for you, please update the web page !
[You will need a username/password to access d0.uni-wuppertal, see here.]  

By the way: 

-  All available software packages can be found on the web at or on ClueD0 (> cd /d0dist/dist/packages).
-  Have a look at the (old) Professor's guide from Heidi.