root@owl-box1:~# cat /proc/swaps 
Filename                                Type            Size    Used    Priority
/dev/sda1                               partition       522104  0       -3
root@owl-box1:~# fdisk -l /dev/sdb | grep sdb1
/dev/sdb1               1          65      522112   82  Linux swap / Solaris
root@owl-box1:~# swapon /dev/sdb1
swapon: /dev/sdb1: Invalid argument