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FlexShare - impact on volumes?

Hello!  I must enable FlexShare on our NetApp 3170 (OnTap 7.3.2).  Does anyone know if enabling FlexShare (priority on) or setting volume priorities (priority set volume vol_name level=High) will cause any interruption to the volume's operation?  Will there be any volume downtime or bump?  The OnTap 7.3 Sys Admin Guide doesn't say one way or another.

Thanks!

TinaS

Re: FlexShare - impact on volumes?

There's no service interruption by setting FlexShare settings.  Of course the priority of volumes will change (on the fly), but one of the points of the product is to never starve a volume regardless of it's priority.

Re: FlexShare - impact on volumes?

One thing to be careful about is that after you enable flexshare, all volumes which have not had their priority explicitly set will all share a default queue or bucket (this is covered in the flexshare best practices guide which you should check out)

In most cases this is absolutely fine, however there are situations with very heavily loaded controllers that a volume which has its priority set to low or very low may actually get more resources allocated to it than the volumes in the default bucket.

This is because once a volume has a priority explicitly set for it, it get's its own queue, its only those volumes which dont have an explicit priority set that have to share their queue.

I personally feel that if you've enabled flexshare, that you should ensure that all new volumes are assigned a priority as standard. Unfortunatley this isnt part of provisioning manager today, however a failry straigthforward script could be created that detects volumes in the default queue and add give them a medium priority.

Regards

John

Re: FlexShare - impact on volumes?

Excellent. I’ve heard of that warning as well. My plan is to set FlexShare volume priority on all volumes.

Thanks for the reply!

Tina