# How can I install a 3TB HDD?



## ghostcorps (Sep 5, 2012)

Hi guys,

 I am trying to install a 3TB Seagate HDD but it is not as easy as I expected... nothing ever is.

Using this thread I have tried the following method:

First I get the disk info:




```
ad12
        512             # sectorsize
        3000592982016   # mediasize in bytes (2.7T)
        5860533168      # mediasize in sectors
        5814021         # Cylinders according to firmware.
        16              # Heads according to firmware.
        63              # Sectors according to firmware.
        W1F03HGG        # Disk ident.
```

Using the thread above I calculate the following to be the correct geometry:


```
[color="Red"]32768[/color]            # sectorsize
        3000592982016    # mediasize in bytes (2.7T)
        [color="red"]5860491264[/color]       # mediasize in sectors
        5814021          # Cylinders according to firmware.
        16               # Heads according to firmware.
        63               # Sectors according to firmware.
        W1F03HGG         # Disk ident.
```

I set this geometry in fdisk though sysinstall:


```
Disk name:      ad12                                   FDISK Partition Editor
DISK Geometry:  5814021 cyls/16 heads/63 sectors = 5860533168 sectors (2861588MB)

Offset       Size(ST)        End     Name  PType       Desc  Subtype    Flags

         0         63         62        -     12     unused        0
        63 5860533105 5860533167   ad12s1      8    freebsd      165
```

I then use newfs to create the filesystem as follows:


```
# newfs -S 4096 -b 32768 -f 4096 -O 2 -U -m 8 -o space -L mediabackup /dev/ad12s1
```

But rather than using the geometry I set previously it uses the following:


```
/dev/ad12s1: 764436.4MB (1565565808 sectors) block size 32768, fragment size 4096
        using 1034 cylinder groups of 740.00MB, 23680 blks, 47360 inodes.
        with soft updates
```

This results in a partition of 735G.

Where did I go wrong?


----------



## SirDice (Sep 5, 2012)

Don't use sysinstall(8), it's deprecated.

The maximum disk size supported by MBR is about 2TB, I suggest you use gpart(8) and the GPT scheme.


----------



## wblock@ (Sep 5, 2012)

That thread is old and somewhat outdated.  Disk Setup On FreeBSD shows how to use gpart(8) to set up aligned GPT partitions.

Fixed drive geometry is an obsolete concept.  Drives put more sectors on the outer tracks because there is more room, and have been doing that for many years.  So trying to calculate an imaginary geometry to satisfy the imaginary geometry used by fdisk(8) is pointless.  GPT is easier and more versatile.


----------



## ghostcorps (Sep 5, 2012)

Thanks for the quick reply guys! 

I'll give that article a go.


----------



## ghostcorps (Sep 5, 2012)

Aaaaand it's done, too easy 

Thanks again guys.


On a sidenote, if anyone is here with the same question you will likely need to destroy the partition before beginning, as explained HERE


----------



## wblock@ (Sep 5, 2012)

ghostcorps said:
			
		

> On a sidenote, if anyone is here with the same question you will likely need to destroy the partition before beginning, as explained HERE



A easier way, without having to delete all the partitions first:
`# gpart destroy -F ada0`


----------

