Compiling Swap space

RW rwmaillists at
Tue Feb 27 13:16:10 UTC 2018

On Tue, 27 Feb 2018 08:09:19 +0000
Steve O'Hara-Smith wrote:

> On 27 Feb 2018 00:23:46 -0500
> "John Levine" <johnl at> wrote:

> > You can also use mdconfig to make an md device backed by a file and
> > swap on that.  That's slower than a swap partition since it has to  
> 	You don't need mdconfig, just make a large file and use
> swapon like this:
> # dd if=/dev/zero of=swapfile bs=1m count=1024
> # swapon swapfile

I tried that and got:

  # swapon swapfile
  swapon: swapfile: Block device required

The word "Block" is presumably out of date, but it does seem to be
saying a device is needed. This was on 11.1.

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