Let /dev/sdb be the volume attached to the server .

mkswap /dev/sdb
swapon /dev/sdb     =>Now swap is added  to the system.

Put entries in /etc/fstab

/dev/sdb swap swap defaults 0 0

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We can see the swap summary using
swapon -s =>usage summary

To turn off swap on a volume do the following.
swapoff /dev/sdb =>turn off swap on this device.