December 18, 2020

Summary

  • File Permissions
    • Basic Permissions
    • Managing Permissions
    • Advanced Permissions
  • Data Transfers
    • Filezilla
    • scp command
    • rsync command

File Permissions: Basic Permissions

Every file and directory has permissions:

  • User: read/write/execute
  • Group: read/write/execute
  • Other: read/write/execute

Permissions are given in the following format:

drwxrwxrwx 1 user group size date filename

File Permissions: Managing Permissions

Change the permissions of a file:

chmod u+x file_name
chmod g+w file_name
chmod o-r file_name

Change the group association of a file:

chgrp groupname file_name

File Permissions: Advanced Permissions

GPFS ACLs

ACLs provide greater control over file permissions

# Get current permissions and store in acls file
mmgetacl /path/to/file > ~/acls.txt

# Edit acls file containing permissions
vim ~/acls.txt

# Apply new permissions to file
mmputacl -i ~/acls.txt /path/to/file

# Delete acls file
rm ~/acls.txt
https://hpcc.ucr.edu/manuals_linux-cluster_security.html#gpfs-acls

Data Transfers: Filezilla

Data Transfers: Filezilla (cont)

Data Transfers: scp command

Using scp on the command line:

Transferring file to the cluster

scp local_file username@cluster.hpcc.ucr.edu:~/directory_name/local_file

Transferring file from the cluster

scp username@cluster.hpcc.ucr.edu:~/directory_name/local_file local_file

Data Transfers: rsync command

Using rsync on the command line:

Transferring file to the cluster

rsync -av --progress FOLDER_A/ username@cluster.hpcc.ucr.edu:~/FOLDER_A/

Transferring file from the cluster

rsync -av --progress username@cluster.hpcc.ucr.edu:~/FOLDER_A/ FOLDER_A/