Debian install and swap

The system is a debian derivative. hdb2 is a primary
partition for Linux swap. /etc/fstab has the entry:

/dev/hdb2 none swap sw 0 0

but top utility shows 0M swap, and attempt to make it active
with swapon (swapon -a) produces the error:

swapon: /dev/hdb2: Invalid argument

Any ideas?


To UNSUBSCRIBE, email to debian-user-REQUEST@xxxxxxxxxxxxxxxx with a subject of "unsubscribe". Trouble? Contact listmaster@xxxxxxxxxxxxxxxx