Hi all
Ok. Before to have a mess of different opinions I want to definitively explain again because I wrote "nonsense", with a smile, remember it :) Very ironically...
Most of us well know what aggregates, flexvols, raid dp or raid 4 are and we don't need to explain. Most of us know that spares, parity disks are not "waste" space for they save your data and very oftern they save more! ;-) But I think that most of people who answered to my first thread did not read well that release note I've linked to it or, almost, they did not read it at all!
The doc very clearly says: with DOT 7.3.1, on a 2020 (and only here), if you want bypass the 8 TB aggregate limit and have a 16TB one (as in other FAS!) you MUST configure a separate aggregate to host ONLY the root volume! Where the unpractical nonsense is? Is that if you have a base 2020 with 12 1 TB SATA and another shelf with 1 TB SATA disks, let say with only other 8 disk (total 20) we will have:
aggr0 - 3 disks RAID-DP with ONLY the root flexvol aggr1 - 9 disks from the base 2020 plus 7 from the shelf, raid-dp, 16 TB raw aggregate with all the other flexvols with user data one spare disk
First aggregate result: 3 TB raw just to host the default minimum size of root volume (roughly 12 GB on a 2020 if I well remember)! This is a nonsense waste! So we cannot, as possible in other systems, use only a couple of parity disk spanning this big aggregate, but we need to couples of that for the root need its own aggregate!
Maybe somebody can observe, as me, that we can create folders, qtrees, eports, shares and luns in the volume marked as root (the so named vol0 in the aggr0) to fill all the available space
Regards! Always with a smile
Da: Glenn Walker [mailto:ggwalker@mindspring.com] Inviato: martedì 20 gennaio 2009 19.29 A: genec220@verizon.net; Milazzo Giacomo; toasters@mathworks.com Oggetto: RE: 7.3.1 and 2020 nonsense :-)
That was my point - having spares is always a good idea and I don't consider it 'waste'. This means the root volume will waste a few GB, like any other volume.
Glenn
________________________________ From: genO [mailto:genec220@verizon.net] Sent: Tuesday, January 20, 2009 12:59 PM To: G.Milazzo@sinergy.it; toasters@mathworks.com Cc: Glenn Walker Subject: RE: 7.3.1 and 2020 nonsense :-)
Giacomo,
You could usea 16TB RAID-DP protected aggregate with multiple flexible volumes, the rootvol being one of those flexvols, as long as you allocate 2 spares.
g
________________________________ From: Milazzo Giacomo [mailto:G.Milazzo@sinergy.it] Sent: Tuesday, January 20, 2009 12:02 PM To: Glenn Walker; toasters@mathworks.com Subject: R: 7.3.1 and 2020 nonsense :-) Maybe something has been not clear for you. The issue is for this nonsense 2020 usage of 7.3.1.
For 2020 and 16TB aggregate only: you must create a SEPARATE aggregate raid dp that will have to contain THE ROOT ONLY, no other volumes, no user data. If you want you could also use R4...but with 2 spares. The result is the same. For a 2020 using 1 TB SATA disk I will waste 3 TB for root!!! Nonsense...unuseful, ridicoulous...what else? :-)
________________________________ Da: Glenn Walker [ggwalker@mindspring.com] Inviato: martedì 20 gennaio 2009 17.27 A: Milazzo Giacomo; toasters@mathworks.com Oggetto: RE: 7.3.1 and 2020 nonsense :-) I don't see the issue:
Create massive aggregate, use RAID-DP and leave 2 spare disks. Put all data in the one aggregate.
We (as a general rule) do not use a separate aggregate for our root volumes - we just maintain a healthy number of spares and use RAID-DP.
Glenn
________________________________ From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Milazzo Giacomo Sent: Tuesday, January 20, 2009 7:09 AM To: toasters@mathworks.com Subject: 7.3.1 and 2020 nonsense :-)
Hi all,
reading this from 7.3.1 release note I've been really beated from this. I was thinking to a 2020 full of 1 TB SATA. To have a 16 TB aggregate I should waste 3 TB for few gigs of root! :) Luckly I don't think that somebody will suggest a 2020 to manage 16 TB of data!!! :)
Bye
Increased aggregate capacity for FAS2020 systems Beginning with Data ONTAP 7.3.1, FAS2020 systems support aggregates up to 16 TB raw capacity, provided that the root volume is hosted in a dedicated aggregate (that is, one that contains only the root volume and no user data). Note: An alternative to maintaining a dedicated root aggregate is to maintain two spare disks. A dedicated root aggregate configuration of three disks is the recommended best practice for all systems. However, if such a configuration is not practical in your environment, you must maintain two spare disks if you configure your FAS2020 system for aggregates larger than 8 TB raw capacity. If you do not configure aggregates larger than 8 TB raw capacity on your FAS2020 system, the conditions for two spare disks or a dedicated root aggregate do not apply. For more information about FAS2020 systems' storage capacity, see the System Configuration Guide.
Dott. Giacomo Milazzo [cid:image001.jpg@01C97B39.56347300] Technical Account Manager Sinergy SpA Filiale di Roma * 00148. viale Castello della Magliana, 38 ' (+39) 3406001045 0665970252 7 +39 02 26922048 * Giacomo.Milazzo@Sinergy.it
