To save yourself some pain, if you've mounted a disk used by an old system, redo to the label or partition table. I've had VTOC Warnings about not having backup labels when doing a simple partition table. So. Run:
# format -e
Choose your new disk.
You'll be presented with: SMI  or EFI .
format> label  SMI Label  EFI Label Specify Label type: 0 Warning: This disk has an EFI label. Changing to SMI label will erase all current partitions. Continue? y Auto configuration via format.dat[no]? n format> quit
SMI will create a new disk slice with backup. backup is the slice logically containing the entire space available on the disk.
When redoing the partition tables on the disk, do not delete or rename backup.
Run format again...
format> partition partition> print Current partition table (original): Total disk cylinders available: 1020 + 2 (reserved cylinders) Part Tag Flag Cylinders Size Blocks 0 unassigned wm 0 0 (0/0/0) 0 1 unassigned wm 0 0 (0/0/0) 0 2 backup wu 0 – 1020 1.99GB (1021/0/0) 4182016 3 unassigned wm 0 0 (0/0/0) 0 4 unassigned wm 0 0 (0/0/0) 0 5 unassigned wm 0 0 (0/0/0) 0 6 unassigned wm 0 0 (0/0/0) 0 7 unassigned wm 0 0 (0/0/0) 0 8 boot wu 0 – 0 2.00MB (1/0/0) 4096 9 unassigned wm 0 0 (0/0/0) 0
In this case, I just want to create one large partition for some extra storage so I will allocate all I can to partition 0. Note that partition 2 is used to reference the entire drive and is not a usable partition. To modify a given partition, just enter the number of the partition at the partition prompt:
Choose the partition, re-name unassigned and make wm.
I like to do the last slice on up, skipping slice 2, taking note of its size... and then when I've made it to 0, give it the same amount of space as slice 2.
partition> label Ready to label disk, continue? y partition> quit format> quit
Create a lovely UFS filesystem...
# newfs /dev/dsk/c0t1d0s0 newfs: construct a new file system /dev/rdsk/c1t1d0s0: (y/n)? y /dev/dsk/c0t1d0s0: 4173824 sectors in 1019 cylinders of 128 tracks, 32 sectors 5000.0MB in 45 cyl groups (23 c/g, 46.00MB/g, 11264 i/g) super-block backups (for fsck -F ufs -o b=#) at:
# fsck -y /dev/dsk/c0t1d0s0
And then mount it however you wish.