/dev/mdctl & deleting md

[Anonymous]

I created a swap space using the following commands

# dd if=/dev/zero of=/swap0 bs=1024k count=256
# chown root:wheel /swap0
# chmod 0600 /swap0

Then I added the following swapfile variable in the /etc/rc.conf file to enable swap file on boot time:
swapfile="/swap0"

# mdconfig -a -t vnode -f /swap0
# swapon /dev/md1

And then I rebooted, now I would like to remove the swap space using the command:

mdconfig -d -u 0

and I get the following message:

mdconfig: ioctl(/dev/mdctl): Device busy

I know that the swapspace is not being used so I was wondering first of all what the problem is and secondly I was curious about what the /dev/mdctl file is used for.

 

[SirDice]

If you look at the output of swapinfo you will see it's in use. Use swapoff to remove the file from the swap. Then you can remove the md device.

 

[Anonymous]

swapoff worked perfectly, thanks