31.5 Adding Swap as a Partition

As an alternative to designating a file as swap space, entire disk partitions may also be designated as swap. The steps to achieve this are largely the same as those for adding a swap file. Before allocating a partition to swap, however, make sure that any existing data on the corresponding filesystem is either backed up or no longer needed and that the filesystem has been unmounted.

Assuming that a partition exists on a disk drive represented by /dev/sdb1, for example, the first step would be to convert this into a swap partition, once again using the mkswap utility:

# mkswap /dev/sdb1

mkswap: /dev/sdb1: warning: wiping old xfs signature.

Setting up swapspace version 1, size = 8 GiB (8587833344 bytes)

no label, UUID=a899c8ec-c410-4569-ba18-ddea03370c7f

Next, add the new partition to the system swap and verify that it has indeed been added:

# swapon /dev/sdb1

# swapon

NAME TYPE SIZE USED PRIO

/dev/dm-1 partition...