Hello,
I have vol0 on netapp F760 (5.3.5) with mixed 18G and 36G disks. I noticed, that there're two disks 36G in the disk group with 18G disks. As I understand, I lose 2x(36-18)=36G of the disk space. Now I added two new 18GB disks to the netapp. My question is how I can replace the 36G disks with the new ones.
Thank you in advance.
~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._. Artur Shnayder Voice: (609)655-5105 x12 System Manager Fax: (609)655-5114 Email: artur@cgen.com Compugen Inc URL: http://www.cgen.com ~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.
----- Original Message ----- From: "Artur Shnayder" artur@cgen.com To: toasters@mathworks.com Sent: Wednesday, November 29, 2000 11:08 AM Subject: Question about disk replacing
Hello,
I have vol0 on netapp F760 (5.3.5) with mixed 18G and 36G disks. I
noticed,
that there're two disks 36G in the disk group with 18G disks. As I
understand,
I lose 2x(36-18)=36G of the disk space.
You should double-check your disk totals to see if this is true.
You only lose space if those 36GB disks were using to reconstructed failed 18GB disks. If they were added normally, what happened should be that one 36GB disk is now the parity drive and the other 36GB disk is fully used. There's no "lost space" other than the parity drive.
You will find this all explained in your sysadmin guide.
Now I added two new 18GB disks to the netapp. My question is how I can replace the 36G disks with the new ones.
If the disks are fully used, you can't replace them with 18GB disks. If they are partially used, you can, but you'll need two more 18GB disks (ones you haven't added yet) and replace them one at a time, through a potentially dangerous raid fail operation. But don't do this until you read the manual and determine the real status of those 36GB drives.
Bruce
artur@cgen.com (Artur Shnayder) writes:
I have vol0 on netapp F760 (5.3.5) with mixed 18G and 36G disks. I noticed, that there're two disks 36G in the disk group with 18G disks. As I understand, I lose 2x(36-18)=36G of the disk space. Now I added two new 18GB disks to the netapp. My question is how I can replace the 36G disks with the new ones.
This depends on how the 36 GB disks got into the volume in the first place. Were they "vol add"ed (in which case their full size will be used and you can't fail them over to smaller discs) or did they get used as a result of 18 GB disks failing (in which case they will be half used, and you can)?
Show us the output of "vol status -r vol0".
Chris Thompson University of Cambridge Computing Service, Email: cet1@ucs.cam.ac.uk New Museums Site, Cambridge CB2 3QG, Phone: +44 1223 334715 United Kingdom.
When you add the first 36GB disk to a raid group with only 18GB disks, the new disk will become parity, freeing up the old 18GB parity disk for data. So you have a gain of only 18GB of space when adding the first 36GB disk. The second 36GB disk will be used in full, giving you another 36GB of space (well, closer to 32 actually, but you get the idea).
Once you have the 36GB disk in there, I don't see any way you can swap it for an 18GB spare. The only way to get rid of it is to create a new volume and copy the data.
Moshe
Artur Shnayder wrote:
Hello,
I have vol0 on netapp F760 (5.3.5) with mixed 18G and 36G disks. I noticed, that there're two disks 36G in the disk group with 18G disks. As I understand, I lose 2x(36-18)=36G of the disk space. Now I added two new 18GB disks to the netapp. My question is how I can replace the 36G disks with the new ones.
Thank you in advance.
~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._. Artur Shnayder Voice: (609)655-5105 x12 System Manager Fax: (609)655-5114 Email: artur@cgen.com Compugen Inc URL: http://www.cgen.com ~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.
Ok, it seems I got the point. The first half of the parity 36G is parity for all 18G and first half of the second 36G. And the second half of the parity 36G is the parity for the second half of the second 36G.
Quoting Moshe Linzer Moshe.Linzer@nsc.com:
When you add the first 36GB disk to a raid group with only 18GB disks, the new disk will become parity, freeing up the old 18GB parity disk for data. So you have a gain of only 18GB of space when adding the first 36GB disk. The second 36GB disk will be used in full, giving you another 36GB of space (well, closer to 32 actually, but you get the idea).
Once you have the 36GB disk in there, I don't see any way you can swap it for an 18GB spare. The only way to get rid of it is to create a new volume and copy the data.
Moshe
Artur Shnayder wrote:
Hello,
I have vol0 on netapp F760 (5.3.5) with mixed 18G and 36G disks. I
noticed,
that there're two disks 36G in the disk group with 18G disks. As I
understand,
I lose 2x(36-18)=36G of the disk space. Now I added two new 18GB
disks to the
netapp. My question is how I can replace the 36G disks with the new
ones.
Thank you in advance.
~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._. Artur Shnayder Voice: (609)655-5105 x12 System Manager Fax: (609)655-5114 Email: artur@cgen.com Compugen Inc URL: http://www.cgen.com ~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.
~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._. Artur Shnayder Voice: (609)655-5105 x12 System Manager Fax: (609)655-5114 Email: artur@cgen.com Compugen Inc URL: http://www.cgen.com ~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.,-*~`^`~*-,._.
-
Artur Shnayder -
Bruce Sterling Woodcock -
Chris Thompson -
Moshe Linzer