First make sure your external disk drive is connected and powered on.
List attached removable storage devices:
$ rmformat -l
Verify the pX partition number that contains the NTFS filesystem, typically "p1", using fdisk. Even though it may seem counterintuitive, include the partition number "p0" as shown by rmformat in fdisk inquiries.
$ pfexec fdisk /dev/rdsk/c6t0d0p0
There are currently 2 sources of ntfs-3g, Openindiana SFE made for installing on top of /dev and working Tuxera and Jean-Pierre André's NTFS-3G project:
As of oi151_a5, ntfsprogs were installed, but not the actual ntfs-3g kernel modules, which will be needed for mounting the NTFS filesystem with read/write capability. To perform this step successfully, you will need to already have the Spec Files Extra Repository (SFE) added to your installation's repository list.
Something is not quite complete about the FUSE install out of the box (thanks DAMIAN WOJSŁAW! http://trochejen.blogspot.com/2011/11/openindiana-and-ntfs-3g.html ).
$ pkg search ntfs-3g
$ pfexec pkg install /system/file-system/ntfs-3g
$ pfexec ln -s /devices/pseudo/fuse\@0\:fuse /dev/fuse
Tuxera and Jean-Pierre André's NTFS-3G:
Working place for ntfs-3g and FUSE is Tuxera's NTFS-3G project that aims at providing a stable NTFS driver for several operating systems.
It is made possible thanks to Jean-Pierre André, on Openindiana page: http://jp-andre.pagesperso-orange.fr/openindiana-ntfs-3g.html (using pkgadd - d *.pkg) Please install 64-bit package on 64-bit installations.
Jean-Pierre André/Tuxera also have an active Advanced NTFS-3G Features project, where you can join in developing more advanced Ntfs features implementation.
Now mount it up
$ pfexec ntfs-3g /dev/dsk/c6t0d0p1 /mnt/backup/
You can now also add a vfstab entry like so:
/dev/dsk/c6t0d0p1 /dev/rdsk/c6t0d0p1 /mnt/backup ntfs-3g - no -