SWAP in file

Commands

#Create a static file
$ dd if=/dev/zero of=/swapfile bs=1M count=1024
1024+0 records in
1024+0 records out

#Fix file mask
chmod 600 /swapfile

#Prepare the file to use as swap
$ mkswap /swapfile
Setting up swapspace version 1, size = 1048572 KiB
no label, UUID=f75cc8f9-78d2-4ea3-945a-eefbd59568ac

FSTAB

echo \/swapfile none swap sw 0 0 >> /etc/fstab