How To create a Swap file in Linux

Once you connected to Linux terminal or putty, with the following steps we can create a swap file.

We need to have the root or sudo privileges to do the same.

To add a swap file:

1. Determine the size of the new swap file in megabytes and multiply by 1024 to determine the number of blocks. For example, the block size of a 64 MB swap file is 65536. (64*1024)

          Mention appropriate count to get correct size of your swap file.

1. At a shell prompt as root, type the following command with count being equal to the desired block size:

dd if=/dev/zero of=/swapfile bs=1024 count=65536

3. Change the permissions of the newly created file:

chmod 0600 /swapfile

4. Setup the swap file with the command:

mkswap /swapfile

5. To enable the swap file immediately but not automatically at boot time:

swapon /swapfile

6. To enable it at boot time, edit /etc/fstab to include the following entry:

/swapfile          swap            swap    defaults        0 0

The next time the system boots, it enables the new swap file.

Cheers!

Bose