3par 8200 change SparingAlgorithm - possible online?

[OAndras]

hello all,

my current config:

3par 8200 / 2 cages / 10 ssd + 38 fc. (cage0 20 FC/ 4 SSD - cage1 18 FC / 6 SSD)

Sparing algorith: maximal

So, now I have only 8 usable SSD disks with 2 spare.

I think, if i change sparing to minimal, i have an additional usable SSD... Is it true?

I found a manual to change sparing:

https://www.hpe.com/h20195/v2/GetPDF.aspx/4AA6-0776ENW.pdf

I can do this changes (setsys + admithw) online? How long does it take about?

thank you / best regards

Andras

[yapkl · Accepted solution]

Hi Andras,

Yes, you are right.

As per the document, if you change to minimal sparing policy it will reserve 1 drive worth subject to minimum 10% for SSD. You can safely change it online and run the admithw command. As indicate in page 7, the sparing change will run in low priority in the background. Exactly how long, I never timed it before (I've done this change online before). Just let it run overnight, it doesn't bother your production workloads.

P/s : I suggest that you capture "showpd -c" output before and after so that you can see how the spare chunklets change after changing to minimal sparing.