2 Replies Latest reply: May 22, 2015 12:03 AM by David Butler RSS

Granite Edge and allocating space on a SteelHead EX data store?

David Butler



I'm fairly new to Granite (SteelFusion) as I work mostly with network related things and not so much storage and backups.  So I apologize for the newbie questions in advance!


I don't have the license to play with this yet, but based on what I've read in the configuration guide.... when setting up Granite Edge on an EX appliance, you are able to allocate this space on the disk.  My question is this.... is there a best practice in setting this up?  Like some sort of percentage of the disk that needs to be allocated for Granite?


Thanks for the assistance that anyone can give me.  thanks!

  • Re: Granite Edge and allocating space on a SteelHead EX data store?
    Tom Tasker

    Hi David,


    The disk space presented in a SteelHead EX (EX) for the Virtual Services Platform (VSP) and Granite / SteelFusion (SF) cannot be chosen by a user defined percentage, instead you get three options via radio button.


    The three options are;


    All to VSP.

    All to SF.

    50% to SF, 50% to VSP. 


    Each one of the options has its merits and reasoning, but you mostly find that you select one based on how you plan to you use you EX appliance.  What is important to remember is that changing the disk space layout will destroy all the data currently on it.  You are moving disk partition tables around and no OS can survive that with all the data intact, so it's deleted and starts all over again.  This should really be a one time operation and then left until a design change forces it. 


    All to VSP.


    As the option implies this will allocate all the HDD space in the EX to the VSP, in effect making one giant datastore for VMware.  This will leave none for SF.  When the storage is all assigned to VSP it become locked into VMware which IMHO then narrows your options.  What happens if you don't want a mega datastore 6 months down the line but want some space for SF?  The answer is you to delete the whole thing and start again. 


    I have only seen this option used once out in the field and this was reversed some months later.


    All to SF.


    The simplest choice for this is; if you're using SF, pick this one!  It assigns all but a small portion of the space (the small bit used for VSP files) to SF and allows you to take full advantage of the SF technology.  What if i need a giant datastore for my VSP?  Not a problem, either create a SF Local Edge LUN or use a SF projected LUN and attach it to the VSP via iSCSI.  Once you're done with the datastore, for whatever reason, you can just decommission the datastore and return the space back to the SF pool. 


    Again in my opinion this is the most versatile and useful disk management mode to use.  You get all the SF space and you can mimic the "All to VSP" mode using the SF LUN options.


    50% to SF, 50% to VSP.


    Never had a single customer choose this as it neither gives the large amount of storage you might need for the VSP, or enough space for SF to be useful.  My advice is to ignore this option completely. 



    To summarize, when you set the disk management for  the EX you get three options.  None of the options is wrong and all have there merits depending on how you are planning to use the technology.  (there is an option for "extended modes" for the options above, but i can go into that if needed.  Long story short is that they just give you more space if it's a first time setup.)  If my customers are using SF then we always go for "All disk space to SF" as it gives the greatest flexibility in terms of usage.