Swap space
Working with swap space:
Creating swap space
In order to get a partition to be swapspace you have to fdisk it as swapspace (type 82), then make it into swap space using
mkswap -L label /dev/sdc1
Once you have done this you enter it into /etc/fstab as
/dev/sdc1 none swap sw 0 0
and then activate it by
swapon -L label
or
swapon -a
Removing swapspace
If it's on a logical volume, first
swapoff -a
or swapoff -L label
then with
swapon -s
you can check which devices are being used for swap.
uncomment it from the /etc/fstab. Should lvm / LVM lvremove give you shit about it being busy you can try dmtools. Unmount the device first, check lsof and fuser as well.
dmsetup uses the /dev/mapper names, not /dev/pvname/lvname.
dmsetup info -c
shows all the devices and if there are files open on it.
dmsetup info -c edgarghost-swap_1
shows the specific device (-c optional)
dmsetup remove --force edgarghost-swap_1
should reset the open file count to 0 (even if it gives a failure) then you can
dmsetup remove edgarghost-swap_1
again.
If none of this works, you can see what's in
/etc/initramfs-tools/conf.d/resume
change the device and then do
update-initramfs -u
and then reboot.