Partition resizing in FreeBSD

I wouldn't suggest running growfs without reading up on it. man stands for manual, so man growfs will present you with the manual to read about it prior to using it.  Though in your case, I am not sure that is what you want.

As an F.Y.I. release 4.8 is considered EOL and no longer supported by the FreeBSD team. However, for whatever reason you may have for continuing to use it, a few more questions need to be answered.

How is your disk currently setup? (at the prompt: df -h  This is the command for display free (space) It will show you your current mount points)

Of those listed, which do you want to grow? Or do you simply want to create a new mount point and use some of the extra space for instance like  /backup?

If you are looking to add a new slice and you are not very familiar with FreeBSD, then backup everything and try the following. (I'm doing this from memory, and it's been awhile since I've played with 4.8)

/stand/sysinstall  at the command prompt will bring you to the FreeBSD installation and Configuration tool.

From there select, Configure

Then select Fdisk

You should then see the Fdisk partition editor. There you will see your disk (Possibly listed as ad0) If you have any unused space, then you can select that slice and hit C to "Create" a slice

Then, select the size you want, for example, 1024M would create a 1 gigabyte slice

Next screen you should see the default partition type of 165 which is a native FreeBSD slice. Click OK

Next you should be able to select your mount point, so for instance /backup

Then you will want to write your changes with w

When you are done with that, you may, again-my memory is a bit hazy, need to edit your fstab so that it mounts the newly created slice on your next boot or with the mount command.  To do so:

(Be careful here)

vi /etc/fstab

then add your newly created /backup.  It will be something similar to:

# Device                Mountpoint      FStype  Options         Dump    Pass#
(other mountpoints will be listed here)
/dev/ad0s1e             /backup            ufs     rw                  2           2

Your device setting probably won't be /dev/ad0s1e just take a note of which disk and slice while you are in Fdisk under /stand/sysinstall.

man fstab at the shell to understand each of the above settings like device, mountpoints, FStype, etc.