Useful Commands

Changing default SHELL

By default every user on RAAD has bash shell configured. If you want to change your default shell to any other, you can follow below procedure;

• Once you logon to RAAD, on head node issue below command to see available shells.

cat /etc/shells

[muarif092@raad ~]$ cat /etc/shells
/bin/sh
/bin/bash
/sbin/nologin
/bin/tcsh
/bin/csh
/bin/zsh
/bin/ksh
[muarif092@raad ~]$

• Decide which shell you want to choose as default and append following lines in your ~/.bashrc file. (Make sure to open at least one parallel session before you do this change, just in case something goes wrong you will still have access to RAAD to revert back the changes. In case something goes wrong and you are not able to login again, edit the .bashrc file from parallel session and revert the changes)

vi ~/.bashrc

• Add below two lines and change /bin/<shell> to as per your requirements. I am changing to tcsh in this case. (do not copy paste)

export SHELL=/bin/tcsh
exec /bin/tcsh

• Logout and logon again and issue below command to see your current shell

ps -p $$

[muarif092@raad ~]$ ps -p $$
  PID TTY          TIME CMD
12345 pts/xx   00:00:00 tcsh
[muarif092@raad ~]$

Check disk utilization

Users home directories are mounted from network storage which is a parallel high performance storage system from Panasas using panFS file system. If you want to check your disk usage on home directory, you can follow below procedure;

• "pan_du" or "du" command can generate usage of your home directory. We suggest using pan_du since it is more optimized for panFS file system. Also "-t" option in pan_du allows you to run utility in parallel which is much faster.
• This is more commonly used, if you want to see overall usage of some directory, you can view summary by simply adding "-s" switch

[muarif092@raad sample]$ pan_du -s -t 4 ~/sample
dir /panfs/vol/m/muarif092/sample: 8 files, 9232 KiB

• To print disk usage of nested directories

[muarif092@raad ~]$ pan_du -t 4 ~/dir01
dir /panfs/vol/m/muarif092/dir01/dir02/dir03: 1 files, 64 KiB
dir /panfs/vol/m/muarif092/dir01/dir02: 3 files, 192 KiB
dir /panfs/vol/m/muarif092/dir01: 4 files, 256 KiB

• To print disk usage of nested directories and files, you can add "-f" option

[muarif092@raad newtests]$ pan_du -f -t 4 ~/dir01
file /panfs/vol/m/muarif092/dir01/dir02/samplefile 64 KiB
dir /panfs/vol/m/muarif092/dir01/dir02/dir03: 1 files, 64 KiB
dir /panfs/vol/m/muarif092/dir01/dir02: 3 files, 192 KiB
dir /panfs/vol/m/muarif092/dir01: 4 files, 256 KiB