Problem on Creating a Swapfile for adding swap space

Question

Folks,
Hello. I am using Oracle Linux 5.6. At this time, the Linux swap space is 0 KB by using the command:
[root@rac1 /]# grep SwapTotal /proc/meminfo
I need 150MB swap space to install Oracle Database. I create the swap space using the following commands:
Step 1:
[root@rac1 /]# dd if=/dev/zero of=/swapfile bs=1024 count15360 hit enter
Output: 153600 to records in
153600 to records out
157286400 bytes(157MB) copied, 3.3835 seconds, 46.5MB/s.
Step 2:
[root@rac1 /]# mkswap /swapfile hit enter
Output: Command not found.
Step 3:
[root@rac1 /]# swapon /swapfile hit enter
Output: Command not found.
Step 4:
[root@rac1 etc]#vi fstab
Add this line into the file: /swapfile swap swap defaults 0 0
Save and close the file fstab.
Step 5:
Reboot Oracle Linux 5.6 and run this command:
[root@rac1 /]# grep SwapTotal /pro/meminfo
Output: SwapTotal: 0 KB
As you see above, swap space is not added. I think the problem is that the commands "mkswap /swapfile" and "swapon /swapfile" are not executed.
My question is : Do any folk understand how to add the swap space successfully ?

Answer 1

When you execute a program, the command shell will walk through the locations specified by $PATH environment variable in order to find it. The "./" path is the current working directory and should not be in the $PATH environment to make sure applications are run only from locations defined by $PATH and not the current working directory. You can bypass this behavior iif you specify the full absolute path to the program at the command prompt, e.g. cd /sbin, ./mkswap or /sbin/mkswap. Other programs and administration tasks will use Linux utilities located in /sbin without specifying the full path and will not work if /sbin is not part of your PATH environment.
You may have seriously screwed up your system because your root account contains /home/ora11g/bin, which is normally defined by .bash_profile located in the user account's home directory. Before analyzing your login scripts, I suggest you post the output of the following command:
cat /etc/passwd