Why is Swap Cento OS 7 not working?

Question

CentOS

Good afternoon.
I put on a clean Swap server through the command:
sudo fallocate -l 4G /swapfile
An error appears that the machine does not know the command: / swapfile. What can be wrong?

Answer 1

This, of course, is not an answer... But why a file and not a partition? A partition is minus the file system overhead...
Well, you can use an alternative: sudo dd if=/dev/zero of=/swapfile bs=1024 count=4194304
PS And what does "does not know the /swapfile command" mean? It's just a filename...