Jim Laurent's Weblog

You may have seen my earlier blog entry on myths and facts about swap space in which I mentioned that ZFS file systems cannot be used for swap files.

# cd /zpool1
# mkfile 10g swapfile
# swap -a /zpool1/swapfile
"/zpool1/swapfile" may contain holes - can't swap on it.

You can, however, use zvols to add swap space onto a ZFS pool:

#
# Add swap partition in the /export/home zfs partition
#
echo "adding zfs swap"
if [ ! -L /dev/zvol/dsk/export/swap ]
then
       echo "creating swap area"
       zfs create -V 1gb export/swap
fi
echo "/dev/zvol/dsk/export/swap -  -  swap  -  no   -" >> /etc/vfstab
/usr/sbin/swap -a /dev/zvol/dsk/export/swap
 

 Thanks to Jim Litchfield for pulling this info from the documentation for zpool