A very basic version of NetApp Usable Space Calculator. Please provide feedback.
March 18, 2014 - Latest version 2.1 - Minor updates to include some new disks and a few disk calculation bugs
Sep 5, 2013 Update: Software Version 2.1. Minor updates - Added 2 new disk sizes ( 1.2 TB SAS & 4 TB SATA )
Aug 8, 2013 Update: I have updated the software version to 2.0 and fixed some bugs.
Also this includes a new feature called Raid Group Size Estimator where you key in disks values, raid type and disk type - the software will attempt to provide the best RG size values either based on NetApp recommendations or Optimal Capacity.(Please note: The Raid group size input in the calculator is only for disk space calculations and this is ignored for the raid group estimator)
I have developed this Raid Group Size Estimator based on many users request. As usual please provide feedback if you do some testing.
Screenshot of new version 2.1 (Software zip attached to this post)
(The below image is a old version. New version available which is 2.1)
There is no assumption on the controllers. Just plain disk calculations. Also for the max/default RAID size, I assume the user using this tool has some idea of the RAID sizes beforehand and will key it in.
Nice tool for those that don't know the math. Some feedback:
* Choice to display capacity in either GB or TB.
* Choosing ONTAP version, because there can be differences in what is allowed or default values. E.g. max raid group sizes are different between ONTAP versions and volume reserve space default space.
* Choice for syncmirror or not.
* Show the actual RAID groups since the RAID group size you choose can have some weird results.
What would make this tool really great is suggesting optimal RAID group sizes for a given number of disks and according to NetApp recommendations. My storage admins seem to struggle the most with deciding on how to do it.
Thank you so much! I also was a bit confused about the following as well:
Say I have 12 total disks, 0 disks allocated for a root volume, 0 allocated as Spare Disks, and have a raid-dp group size of 6.
I noticed that Usable Capacity was decreased if I added disks to the Disks Allocated For Root Volume field even though I have plenty of disks left from the total of 12 to not take away from the Raid Group size of 6.
The same is true if I increase the number of spare disks. Each additional spare disk takes away from Usable Capacity even if there are plenty of available disks with a Raid Group size of 6.
I understand on the one hand that the tool just does plain disk calculations, but on the other hand it leaves me wondering what the Raid Group Size is used for then. (Or maybe a better way to put it is, how should I properly use the Raid Group Size value in the way you intended.)