Thanks all for answers. They're quite what I was thinking about "physics" :) Also if I could use "fail/unfail" the raid group I operate is always the same...so that I could remove a disk from it but this last want back a disk :)
And all this stuff for the customer is worried about the overall performances. He's got now three rg, the first with 20, the second with 26 and the last with 6 disks and he's concerned about performances gave by the smaller rg influencing all the aggregate...
Da: Davin Milun [mailto:davin.milun@gmail.com] Inviato: sabato 27 novembre 2010 14:55 A: Milazzo Giacomo Cc: toasters@mathworks.com Oggetto: Re: Is there's a way to remove and reassign a disk?
No - you're stuck with your raidgroup configuration, short of destroying the aggr.
If it really was just a specific incorrect DISK that was used, and you wanted to use another, you could use "disk replace" to do that - but that won't let you change raidgroup layout.
Davin. On Sat, Nov 27, 2010 at 5:17 AM, Milazzo Giacomo <G.Milazzo@sinergy.itmailto:G.Milazzo@sinergy.it> wrote: Hi all,
In my experience I think is not possibile but a customer of mine has this issue. He wanted to extend the two raid group of his aggregate but once increased the raid group size he forgot to use the syntax:
aggr add -d x.y -g raidgroup name
So the last raid group has been extended and another raid group has been created with only 5 disks... He asked me how to go back and my answer is: "Copy the data, destroy the aggr and recreate it..." :)
But I remember that times ago a customer of mine used the "disk fail" command just to try it and (not sure on syntax) he was able to "unfail" the disk. So, what, for this case, if "disk fail" is used to fail the disk, rebuild its data on a spare, the unfail the failed, zeroed and manually assigned to the right raid group?
Dott. Giacomo Milazzo [cid:image001.jpg@01CB8E48.29D11970] Technical Account Manager Sinergy SpA Filiale di Roma * 00198. viale Regina Margherita, 269 ' (+39) 3406001045 0644245272 7 (+39) 0226922048 * Giacomo.Milazzo@Sinergy.it
Performance with a RG of 20, 26, and 6 is not ideal, but it probably will not cause problems. There is no guarantee, but even if there was a RG of only 3, it is difficult to measure a performance problem.
The primary exception is when data turns over very slowly. If the data change is very slow, the smaller RG can become hot spots. It is still likely there will be few problems with an RG of 6.
From: Milazzo Giacomo [mailto:G.Milazzo@sinergy.it] Sent: Saturday, November 27, 2010 2:32 PM To: Davin Milun Cc: toasters@mathworks.com Subject: R: Is there's a way to remove and reassign a disk?
Thanks all for answers.
They're quite what I was thinking about "physics" J
Also if I could use "fail/unfail" the raid group I operate is always the same...so that I could remove a disk from it but this last want back a disk J
And all this stuff for the customer is worried about the overall performances. He's got now three rg, the first with 20, the second with 26 and the last with 6 disks and he's concerned about performances gave by the smaller rg influencing all the aggregate...
Da: Davin Milun [mailto:davin.milun@gmail.com] Inviato: sabato 27 novembre 2010 14:55 A: Milazzo Giacomo Cc: toasters@mathworks.com Oggetto: Re: Is there's a way to remove and reassign a disk?
No - you're stuck with your raidgroup configuration, short of destroying the aggr.
If it really was just a specific incorrect DISK that was used, and you wanted to use another, you could use "disk replace" to do that - but that won't let you change raidgroup layout.
Davin.
On Sat, Nov 27, 2010 at 5:17 AM, Milazzo Giacomo G.Milazzo@sinergy.it wrote:
Hi all,
In my experience I think is not possibile but a customer of mine has this issue.
He wanted to extend the two raid group of his aggregate but once increased the raid group size he forgot to use the syntax:
aggr add -d x.y -g raidgroup name
So the last raid group has been extended and another raid group has been created with only 5 disks...
He asked me how to go back and my answer is: "Copy the data, destroy the aggr and recreate it..." J
But I remember that times ago a customer of mine used the "disk fail" command just to try it and (not sure on syntax) he was able to "unfail" the disk.
So, what, for this case, if "disk fail" is used to fail the disk, rebuild its data on a spare, the unfail the failed, zeroed and manually assigned to the right raid group?
Dott. Giacomo Milazzo
Technical Account Manager
Sinergy SpA Filiale di Roma + 00198. viale Regina Margherita, 269
' (+39) 3406001045 0644245272
7 (+39) 0226922048 - Giacomo.Milazzo@Sinergy.it
This is also my opinion considering also other conditions. After all WAFL spread data all over the aggregate and in this case over 56 mechanics (300 GB 15k rpm FC disks) Thanks a lot for the update.
Da: Steiner, Jeffrey [mailto:Jeffrey.Steiner@netapp.com] Inviato: sabato 27 novembre 2010 16:08 A: Milazzo Giacomo; Davin Milun Cc: toasters@mathworks.com Oggetto: RE: Is there's a way to remove and reassign a disk?
Performance with a RG of 20, 26, and 6 is not ideal, but it probably will not cause problems. There is no guarantee, but even if there was a RG of only 3, it is difficult to measure a performance problem.
The primary exception is when data turns over very slowly. If the data change is very slow, the smaller RG can become hot spots. It is still likely there will be few problems with an RG of 6.
From: Milazzo Giacomo [mailto:G.Milazzo@sinergy.it] Sent: Saturday, November 27, 2010 2:32 PM To: Davin Milun Cc: toasters@mathworks.com Subject: R: Is there's a way to remove and reassign a disk?
Thanks all for answers. They're quite what I was thinking about "physics" :) Also if I could use "fail/unfail" the raid group I operate is always the same...so that I could remove a disk from it but this last want back a disk :)
And all this stuff for the customer is worried about the overall performances. He's got now three rg, the first with 20, the second with 26 and the last with 6 disks and he's concerned about performances gave by the smaller rg influencing all the aggregate...
Da: Davin Milun [mailto:davin.milun@gmail.com] Inviato: sabato 27 novembre 2010 14:55 A: Milazzo Giacomo Cc: toasters@mathworks.com Oggetto: Re: Is there's a way to remove and reassign a disk?
No - you're stuck with your raidgroup configuration, short of destroying the aggr.
If it really was just a specific incorrect DISK that was used, and you wanted to use another, you could use "disk replace" to do that - but that won't let you change raidgroup layout.
Davin. On Sat, Nov 27, 2010 at 5:17 AM, Milazzo Giacomo <G.Milazzo@sinergy.itmailto:G.Milazzo@sinergy.it> wrote: Hi all,
In my experience I think is not possibile but a customer of mine has this issue. He wanted to extend the two raid group of his aggregate but once increased the raid group size he forgot to use the syntax:
aggr add -d x.y -g raidgroup name
So the last raid group has been extended and another raid group has been created with only 5 disks... He asked me how to go back and my answer is: "Copy the data, destroy the aggr and recreate it..." :)
But I remember that times ago a customer of mine used the "disk fail" command just to try it and (not sure on syntax) he was able to "unfail" the disk. So, what, for this case, if "disk fail" is used to fail the disk, rebuild its data on a spare, the unfail the failed, zeroed and manually assigned to the right raid group?
Dott. Giacomo Milazzo [cid:image001.jpg@01CB8E53.2E5281E0] Technical Account Manager Sinergy SpA Filiale di Roma * 00198. viale Regina Margherita, 269 ' (+39) 3406001045 0644245272 7 (+39) 0226922048 * Giacomo.Milazzo@Sinergy.it
-
Milazzo Giacomo -
Steiner, Jeffrey