I've seen that sometimes the entry for the swapfile in fstab is specified as "none" for the mount point and sometimes as "swap" instead. For example:
/swapfile none swap defaults 0 0 /swapfile swap swap defaults 0 0 The fsrtab man page says that "none" should be used, but Red Hat's documentation uses "swap" instead.
What is the difference between those two?
It's only a name. You can use any string, for example: pinkunicorn.
I think the following may be useful: "All about Linux swap space"
Since swap space is a special type of filesystem, many of these parameters aren’t applicable. For swap space, add:
/dev/hdb1 none swap sw 0 0 where /dev/hdb1 is the swap partition. It doesn’t have a specific mount point, hence none. It is of type swap with options of sw, and the last two parameters aren't used so they are entered as 0.
The /etc/fstab entry for a swap file would look like this:
/swapfile none swap sw 0 0 
fstab? Generally, the second field of thefstabis thename, which is usually a pathname to mount on. A swap partition does not have a pathname, so it has no meaning here. You could name it "gobbledegook" and the mounter will not care. The use of 'none' or 'swap' are just conventions, and may aid some tools in managing such partitions.