Group 1 : Grid Computing Laboratory of Information Technology Supervisors: Alexander Ujhinsky Nikolay Kutovskiy

Outline Why using Grid Computing? Practice Description Pre-requisites. Procedures Login to UI Creating Required Files Submitting Job Checking the Job States Retrieving the Output Files

Why Grid Computing? Reduction in the calculation time Reduction in costs Reliable and secure data management Effective usage of the hardware and software Ability to use scalable computer resources Ability to integrate and use distributed resources of organization

Practice Description Given: movie file (*.avi). It's placed in the grid on the following path: guid:3f706ca8-fcd3-46fd-a8f4-e3525fcec7db lfn:/grid/edu/course/movie.lfn Required: Write a script to do the following: upload the file to the appropriate working nod convert the movie using ffmpeg utility (use flags in Requirements to find the appropriate host) save converted file to a Storage Element and submit it to the grid.

Pre-requisites: Should have a valid personal digital certificate (it is a long lived certificate identifying individuals like passport and commonly used between web browsers to authenticate sites). Should be registered with at least one virtual organization (edu in our case). Should have an account on the grid user interface (vps101.jinr.ru). Should have a SSH client to access the grid UI (Putty Tool). should have a valid proxy certificate (It is a short lived certificate to reduce the vulnerability and can act on the user’s behalf).

Procedures: 1. Login to the grid UI This is done by using the Putty tool vps101.jinr.ru

Then you will be asked for your account information as Username and Password.

You can check the existence of a valid proxy certificate

Through the UI, Now I can: Interact with the data management facilities Submit jobs Check Job States Retrieve the output of the jobs Cancel jobs

2.Creating shell and JDL Files To create a shell file Type vi file_name.sh in Putty command window vi video.sh lcg-cp -v lfn:/grid/edu/course/movie.lfn file:movie.avi ffmpeg -i movie.avi -ar c_movie.flv lcg-cr --vo edu file:c_movie.flv -l lfn:/grid/edu/myehia/c_movie_V2.lfn This command copies the movie file from the grid to the UI This command uses ffmpeg tool to convert the video file from avi format to flv format. This command saves the new video file to the grid.

Then create a JDL file by using the same command vi video.jdl Type = "job"; JobType = "Normal"; Executable = "video.sh"; Environment = {"LFC_HOST=vps104.jinr.ru"}; StdOutput = "video.out"; StdError = "video.err"; OutputSandbox = {"video.out","video.err"}; InputSandbox = {"video.sh"}; Requirements = Member("ffmpeg",other.GlueHostApplicationSoftwareRunTimeEnviro nment); Type of the request described by the JDL The type of the job described by the JDL. The file to be executed The environment which is needed by the job to run properly It represents the job requirements on resources. The file name where the standard output of the job is saved. The file name where the standard error of the job is saved. List of strings identifying the list of files generated by the job on the WN, which have to be retrieved List of strings identifying the list of files on the UI local disk needed by the job for running and hence needed to be transferred from the UI to the CE.

3.Submitting the Job This can be done by using the command: After Submitting the Job Successfully glite-wms-job-submit -a -o job.id video.jdl

4.Checking Job State

4.Retrieving Output Files Once the job is terminated successfully with exit code = 0, you can retrieve the output files by using the following command:

Reading output files

The Difference Between the Original Movie File and the New One.

Acknowledgment Thanks to: Alexander Uzhinskiy Nikolay Kutovskiy For their Great Effort and Help During the Last Three Weeks Thanks to JINR Staff for their Care. Thank You All