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Contact Information

• Michael D. Gardner
• Graduate Student
• Office: Physics 395
• Email
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• Department of Physics
• University of California
• One Shields Ave.
• Davis, CA 95616

CMS Journal

Getting Started

I got started a long time ago, and so much of this has long been forgotten. I.ve had a few people look this over, to see if there is anything else that could be added, but nothing so far.

Getting registered with CMS:

In getting a computer account, you first have to get registered with CMS. Supposedly the description of how this should be done is explained in the WorkBookGetAccount twiki. Following this is probably a better idea than what I did (which was a mismatch of following the twiki and asking people for help), but I didn.t know any better, so what I did was:

• I requested an account on October 1st, by filling out everything that was required in: CMS Registration.
• I scanned the info page of my passport and e-mailed it to the admin I was pointed to: anastasia.dolya@cern.ch
• I was told that this could take a while, so I waited 4 weeks. After a month, I hadn.t heard anything back about it, so I asked someone working at CERN about it. I was told to write to CMS computing to check on the status of my account (CMS.Computing@cern.ch).
• After about a week I hadn.t heard back anything, except that there was another Michael Gardner registered at CERN. Not sure if that slowed things down or not. Finally, on November 10th, I received a message from cms.people@cern.ch (which was copied to cms.register@cern.ch), outlining what I needed to do in order to open a Computing Account in CMS. This was the message I received:

Dear Gardner Michael (UCDAVIS),

You are now registered in CMS as 'Graduate Student' from your institute (UCDAVIS).

Now you have to open a Computer Account in CMS (group ZH). Send an email to cms.computing@cern.ch with all the following information about yourself:

• full family name
• first name
• birth date (day-month-year)
• your CERN id number if already known
• your previous login name (if any, whatever old)
• preferred login name (min 3, max 8 characters)

BEWARE: once the account is created you have only 5 days to change the temporary password. Once your CERN and CMS registrations are OK, you will be contacted by email for the next steps for your account.

Take note of the rules in Use of CERN computing facilities http://computingrules.web.cern.ch/ComputingRules. In particular, please have a look at the rules about P2P applications http://security.web.cern.ch/security/software-restrictions forbidden to use at Cern (e.g. Skype, KaZaA,...)

Best regards,

CMS secretariat

Once you get the CMS computing account, you can log in to your account with: ssh yourloginname@lxplus.cern.ch

Note that this can be done in the terminal for Mac and Linux users, and for Windows users, the best ssh client I have found is PuTTY. If you want to do anything graphical, make sure that you include the -X option (which will require you to have set up Xming with PuTTY, which instructions are here).

At this point you will be asked for your temporary password. You will want to quickly change your password. This can be done here, along with changing a variety of aspects of your account.

First things to do:

Now that you have an account that you can log into, you can set up a CMSSW release on lxplus. This can be done by first finding the releases that are available with: scramv1 list CMSSW

You should note that the list of CMSSW releases that show up will be tied to the value that you have for SCRAM_ARCH. More precisely:

• For CMSSW versions 5_1_3 and above, "setenv SCRAM_ARCH slc5_amd64_gcc462"
• For CMSSW versions 4_1_X and above, "setenv SCRAM_ARCH slc5_amd64_gcc434"
• For older CMSSW versions, "setenv SCRAM_ARCH slc5_ia32_gcc434"

Once you have set your SCRAM_ARCH and found the CMSSW release you want, you can set it up with: cmsrel CMSSW_X_Y_Z

Then you can start working in the directory. You can check out packages that are saved: cvs co Folder/SubFolder

• you can find the details of the various folders using either: The LXR Cross Referencer or Index of CMSSW. Also, you can add options for how you check out the package. For example, if you want to check out a certain release, you put: cvs co -r V00-00-00 Folder/SubFolder
• Or if you want to check out a package from someone's UserCode directory, but still have it in the standard setup (Folder/SubFolder), you can use the option: cvs co -d Folder/SubFolder UserCode/name/.../Folder/SubFolder
• You then want to make sure that any environment variables that are being used are consistent with what you want them to be for the package you're using. You'll go into the Folder: cd CMSSW_X_Y_Z/src/Folder
• And then you'll have the environment variables set: cmsenv (I have run into so many problems just because I have forgotten to run cmsenv).
• And then you'll have the environment variables set: cmsenv (I have run into so many problems just because I have forgotten to run cmsenv).

If everything has been built, you can then try to run a python file: cmsRun yourConfig.py

If you haven't built everything yet in the release, then you need to run 'scramv1 b' when you are in the 'src'. In order to "unbuild", you can run 'scramv1 b clean'.

I find that the most helpful shell to use is bash, but the lxplus accounts are default with tcsh. You can check your current shell with ps -p $$, and change your shell each time with bash -l. If you want to change the default for your account, you can go to your cern account and:

• Click on the link "Applications and Resources"
• Click on [Manage] corresponding to the "Linux and AFS" line within "Common Services".
• Under "Linux settings" section, you can select your Unix Shell between: /bin/tcsh, /bin/bash, /bin/csh, /bin/ksh, /bin/sh and /bin/zsh.
• Press on the "Save Selection" blue button to activate your change. Wait for about an hour to make sure the change is propagated to the Linux environment.

With commands you may run a ton of times, it will be helpful to change the .cshrc/.bashrc files (depending on whether your account is set up for bash or csh, which it begins with csh), adding aliases, for example two helpful ones for me are:

• alias ls='ls -C --color'
• alias b='scramv1 b -j4'

Getting Grid certificate:

One of the common things required in CMS is getting a GRID Certificate. In order to this you need to get a personal certificate and you need to register to the CMS VO (which requires a CERN lxplus account).

You need to get a personal certificate signed by a CMS-registered Certificate Authority here. In my case it was John Conway, but currently it is Maxwell Chertok. You can find who to contact here. You can find the procedures summarized here.

The following steps did not go as smoothly as I thought that they would. I tried to follow what was done here so I hope it goes more quickly for you than it did for me. I made a few minor mistakes along the way, so had to carry out many of the tasks twice.

• Go to DOEGrids CA import and follow the instructions to import DOEGrids as a Certificate Authority into your browser. You only need to do this once.
• Go to DOEGrids PKI and click on "New User" under the enrollment tab. Fill out the appropriate fields; the affiliation/registration authority field should be OSG, the VO Name is CMS, and your sponsor is the member of the USCMS certificate team that you contacted. In the comments section, add "USCMS".
• Be patient. The OSG Registration Authority needs to verify that you are who you say you are before they are allowed to issue a certificate. Once all of this goes through, you can get the grid certificate set up for your lxplus account by following the instruction here.

Summary from a Twiki