Commands for System Statistics (UNIX)

Regular Resource Monitoring UNIX Commands:

1. iostat
2. free
3. mpstat
4. sar
4. ps -aux
5. ps -eo pcpu,pid,user,args | sort -r -k1 | less
6. ps -eo pid,pcpu,comm
7.ps -eo pid,pcpu,user,cmd | awk '{if ($3 == "h06adm") print }'
8. fdisk -l | grep Disk  - Display total hard disk size
9. df -h - Display disk free in Human understandable format (In GB)
10. cat /proc/cpuinfo  ( To check the CPU Core)
11. lscpu (to check the cpu)
12. /hwinfo  - To get hardware details
13. /usr/sbin/dmidecode - To get the internals of hardware
14. cat /proc/meminfo   or   free -g   (To check Ram)
15. Sed (2/String1/String2) - String editor to replae
16. mpstat -p All  - To check each core of cpu

Example shell Program:

#!/bin/sh

ps -eo pid,pcpu,comm | awk '{if ($2 > 4) print }' >> ~/ps_eo_test.txt

#!/bin/bash

# by Paul Colby (http://colby.id.au), no rights reserved ;)

PREV_TOTAL=0

PREV_IDLE=0

while true; do

  CPU=(`cat /proc/stat | grep '^cpu '`) # Get the total CPU statistics.

  unset CPU[0]                          # Discard the "cpu" prefix.

  IDLE=${CPU[4]}                        # Get the idle CPU time.

  # Calculate the total CPU time.

  TOTAL=0

  for VALUE in "${c...@]}"; do

    let "TOTAL=$TOTAL+$VALUE"

  done

  # Calculate the CPU usage since we last checked.

  let "DIFF_IDLE=$IDLE-$PREV_IDLE"

  let "DIFF_TOTAL=$TOTAL-$PREV_TOTAL"

  let "DIFF_USAGE=(1000*($DIFF_TOTAL-$DIFF_IDLE)/$DIFF_TOTAL+5)/10"

  echo -en "\rCPU: $DIFF_USAGE%  \b\b"

  # Remember the total and idle CPU times for the next check.

  PREV_TOTAL="$TOTAL"

  PREV_IDLE="$IDLE"

  # Wait before checking again.

  sleep 1

done

Secure Copy of UNIX

Example syntax for Secure Copy (scp)

What is Secure Copy?

scp allows files to be copied to, from, or between different hosts. It uses ssh for data transfer and provides the same authentication and same level of security as ssh.

Examples

Copy the file "foobar.txt" from a remote host to the local host

$ scp your_username@remotehost.edu:foobar.txt /some/local/directory

Copy the file "foobar.txt" from the local host to a remote host

$ scp foobar.txt your_username@remotehost.edu:/some/remote/directory

Copy the directory "foo" from the local host to a remote host's directory "bar"

$ scp -r foo your_username@remotehost.edu:/some/remote/directory/bar

Copy the file "foobar.txt" from remote host "rh1.edu" to remote host "rh2.edu"

$ scp your_username@rh1.edu:/some/remote/directory/foobar.txt \ your_username@rh2.edu:/some/remote/directory/

Copying the files "foo.txt" and "bar.txt" from the local host to your home directory on the remote host

$ scp foo.txt bar.txt your_username@remotehost.edu:~

Copy the file "foobar.txt" from the local host to a remote host using port 2264

$ scp -P 2264 foobar.txt your_username@remotehost.edu:/some/remote/directory

Copy multiple files from the remote host to your current directory on the local host

$ scp your_username@remotehost.edu:/some/remote/directory/\{a,b,c\} .

$ scp your_username@remotehost.edu:~/\{foo.txt,bar.txt\} .