# how much storage space will I get if I use ***Gbyte drives?

• ### Question

• 12 drives total
250 GB each (all same specs)

The first two drives will be a RAID 1 using the standard setup.

20 GB for the OS and roughly 200 GB for the landing.

In my example, the 10 remaining drives total about 2.5 TB.  Is that what will be available or is it half?

What is the formula for calculating the total storage space offered for different capacities of drives?

An .xls file to drop in drive capacity to see what you will end up with would be really useful for me to explain to customers how it may be better to add fewer larger drives than a bunch of smaller drives.

A ROI for storage considerations.

Staple Bench Computers
Wednesday, October 8, 2008 10:38 AM

### Answers

•  In my example, the 10 remaining drives total about 2.5 TB.

Actually, it uses the 200 GB for the "landing" you suggested as well.  Total: ~2.7 TB FREE.  But remember, WHS uses the ISO standards for calculating free space.  So a 250GB HDD is really only about 237GB.  Taking that into account, and you will see about 2.43 TB available when you are all said and done.

Is that what will be available or is it half?

If you turn on Duplication for ALL of your shared folders, it will still show 2.43 TB FREE.  But when you copy 1 TB, you will lose about 1.8TB of free space.  I.e., duplicate everything you can't live without.  Leave the share for downloaded media files in a folder that is "not" set to duplicate.

What is the formula for calculating the total storage space offered for different capacities of drives?

Drive XX Total + Drive XX Total + Drive XX Total = Absolute total available.  There is no "formula".  Just duplication which is like RAID 1, but only for the Shared Folders you enable (see my screenshot in this post for my folders I enabled and disabled for Duplication for an example).

An .xls file to drop in drive capacity to see what you will end up with would be really useful for me to explain to customers how it may be better to add fewer larger drives than a bunch of smaller drives.

A ROI for storage considerations.

Not needed.  I was in your shoes too, until I searched these forums.  The answer has been there, many times over.  The WHS Storage Pool simply adds new HDDs to the entire pool.  Whatever is the capacity of that new HDD, will increase your overall FREE space.

Only "Duplication" duplicates the storage requirement for that file you are storing.  So for a 10 MB file, it will take up about 20 MB.  But remember, ISO standards means a 10 MB file is really 8.79 MB, so only about 17.6 MB will be used by the new numbers.

Remember that whole 1024 bytes = 1000 real bytes sticker on the box of the hdd you bought?  There ya go.

Eric A. Duncan http://eduncan911.com
Wednesday, October 8, 2008 4:42 PM

### All replies

•  In my example, the 10 remaining drives total about 2.5 TB.

Actually, it uses the 200 GB for the "landing" you suggested as well.  Total: ~2.7 TB FREE.  But remember, WHS uses the ISO standards for calculating free space.  So a 250GB HDD is really only about 237GB.  Taking that into account, and you will see about 2.43 TB available when you are all said and done.

Is that what will be available or is it half?

If you turn on Duplication for ALL of your shared folders, it will still show 2.43 TB FREE.  But when you copy 1 TB, you will lose about 1.8TB of free space.  I.e., duplicate everything you can't live without.  Leave the share for downloaded media files in a folder that is "not" set to duplicate.

What is the formula for calculating the total storage space offered for different capacities of drives?

Drive XX Total + Drive XX Total + Drive XX Total = Absolute total available.  There is no "formula".  Just duplication which is like RAID 1, but only for the Shared Folders you enable (see my screenshot in this post for my folders I enabled and disabled for Duplication for an example).

An .xls file to drop in drive capacity to see what you will end up with would be really useful for me to explain to customers how it may be better to add fewer larger drives than a bunch of smaller drives.

A ROI for storage considerations.

Not needed.  I was in your shoes too, until I searched these forums.  The answer has been there, many times over.  The WHS Storage Pool simply adds new HDDs to the entire pool.  Whatever is the capacity of that new HDD, will increase your overall FREE space.

Only "Duplication" duplicates the storage requirement for that file you are storing.  So for a 10 MB file, it will take up about 20 MB.  But remember, ISO standards means a 10 MB file is really 8.79 MB, so only about 17.6 MB will be used by the new numbers.

Remember that whole 1024 bytes = 1000 real bytes sticker on the box of the hdd you bought?  There ya go.

Eric A. Duncan http://eduncan911.com
Wednesday, October 8, 2008 4:42 PM
• Hello,
I am pretty sure, that buying 2 or (better) 3 big drives would pay off:
- less power consumption
- better overview in case of a disk failure (and less risk of disk failure)
- less noise
- more remaining possibilities to add modern disks as needed

Best greetings from Germany
Olaf
Wednesday, October 8, 2008 5:15 PM
• Olaf is correct about power consumption. In addition, newer drives comsume less power per drive, so a 3 year old 200 GB drive will probably consume significantly more than a brand new 1 TB drive.

As for disk usage, you have access to 100% of the space on every drive in the storage pool. Backups, application folders (a concept that allows a WHS add-in to store persistent information outside the shares), duplication, and the file shares will all use space in the storage pool, but there's no simple formula that will tell you how many GB of data you'll be able to store for a given size of storage pool. Every home's backup requirements will be different, for example, and the backup database often doesn't increase in size much after the first several backups. So your backup database might be 100 GB, but mine might be 200 GB for the same number of PCs. And the same for the shares: duplication will effectively use 2 bytes of space for every byte of file size, but the number and type of files will have an effect on how they'll be distributed on disk, and therefore how the storage pool will react. If duplication is only turned on for some shares, it gets more complex. Et cetera.

I'm not on the WHS team, I just post a lot. :)
Thursday, October 9, 2008 8:36 PM