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We will now explore the different options when it comes to storing your data.

Main filesystems

1. Connect to Atos HPCF or ECS main login node. What is your default filesystem? Can you try 4 different ways to accessing that space?

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   title Answer
   The default directory is your HOME directory, which is /home/$USER. It is a dedicated personal space for you, and you can always come back to that with either of the following commands: No Format cd cd ~ cd $HOME cd /home/$USER Your HOME directory is accessible across all Atos HPCF, ECS, VDI and EcFlow services.

   
   

2. There are 3 more main storage spaces. Create an empty file called del.me on each one of them. Then,  check that they have been created with ls, and then remove them with rm.

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   title Answer
   Besides HOME, you also have also access to PERM, HPCPERM and SCRATCH. Like HOME, they are all dedicated personal spaces with their corresponding environment variable. Using those environment variables over hardcoded paths is strongly recommended. You can use touch to create the test files: No Format touch $PERM/del.me touch $HPCPERM/del.me touch $SCRATCH/del.me Check they exist with: No Format ls -l $PERM/del.me ls -l $HPCPERM/del.me ls -l $SCRATCH/del.me Remove them with: No Format rm $PERM/del.me rm $HPCPERM/del.me rm $SCRATCH/del.me

   
   

3. How much space have you used in each of your main 4 filesystems? How much can you store?

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   title Answer
   All the filesystems have quotas enforced. You can check them with the quota command No Format quota For HOME and PERM, the snippet should look similar to: No Format Quota for $HOME: home_b             user    1234        <space used>   <space limit>       <number of files stored>       -   * Quota for $PERM POSIX User      1234    <space used>   <space limit>       <number of files stored>       none For SCRATCH and HPCPERM the format is slightly different: No Format Project quota for $SCRATCH and $SCRATCHDIR: Disk quotas for prj 1000001798 (pid 1000001798): Filesystem used quota limit grace files quota limit grace /ec/res4 XXX YYY YYY - ZZZ WWW WWW - Project quota for $HPCPERM: Disk quotas for prj 2000001798 (pid 2000001798): Filesystem used quota limit grace files quota limit grace /ec/res4     XXX YYY YYY - ZZZ WWW WWW -

   
   

4. If you are on the VDI, open a new terminal there. Can you access your HOME, PERM, SCRATCH and HPCPERM ?

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   title Answer
   HOME and PERM are NFS-based Filesystems, which are mounted on all user computing platforms at ECMWF. You may access them with $HOME and $PERM environment variables: No Format ls $HOME ls $PERM However, SCRATCH and HPCPERM  are Lustre Based filesystem only available on the Atos HPCF, so  they are not available on other computing platforms such as VDI or ecFlow VMs and the corresponding environment variables are therefore not defined.

   
   

5. EXTRA: For long term archival purposes, most users may also use ECFS. Files will be stored in ECMWF's Data Handling System on Tape. Create a small text file and copy it to your ECFS space, then ensure it is there, retrieve it and remove it.

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   title Solution
   No Format echo "hello world" > test_file.txt ecp test_file.txt ec: els -l ec:test_file.txt ecp ec:test_file.txt retrieved_test_file.txt diff test_file.txt retrieved_test_file.txt erm ec:test_file.txt

   
   

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