Re: Mixing 512-byte sector, and 4096-byte sector drives

Previous thread: mdadm RAID and drives spinning up/down by Mark Knecht on Sunday, March 21, 2010 - 2:40 pm. (2 messages)

Next thread: Questions regarding startup of imsm container by Randy Terbush on Monday, March 22, 2010 - 8:56 pm. (20 messages)
From: Peter Kieser
Date: Monday, March 22, 2010 - 4:39 pm

Hello,

I have a 6-drive RAID6 of WD15EADS (512-byte sector) drives. One of the 
drives is failing, and I have been forced to buy a WD15EARS (4096-byte 
sector) drive to replace the failing drive, and it has the new "advanced 
format" technology.

Do I need to set the "XP" jumper on pins 7-8 to play nicely with the 
other 512-byte sector drives in my array, or will mdraid be okay with 
the 4096-byte sector drive? Will there be a performance penalty adding 
the drive to my array?

Thank you,

-Peter
--

From: Wil Reichert
Date: Monday, March 22, 2010 - 5:11 pm

Did you create your RAID on the device or on a partition?  If its on
the entire device then you should be fine, tho this might depend on
which metadata format you are using & where its located on the disc
(not sure how the metadata effects data alignment).  If you used a
standard partitioning tool its likely your partitions start on sector
63.  This can be confirmed via an fdisk -l on your other drives.  If
that's the case then you'll probably want to use the offest jumper.
How the drive will behave with the others I have no idea.  If after
you add the drive and your write speeds drop dramatically then
something is misaligned.

Wil
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From: Peter Kieser
Date: Tuesday, March 23, 2010 - 11:53 am

I created the RAID directly on the device, I have replaced the drive and 
the new 4096-byte drive seems to be playing nicely with the other drives 
in the array after the resync completed.

-Peter
--

Previous thread: mdadm RAID and drives spinning up/down by Mark Knecht on Sunday, March 21, 2010 - 2:40 pm. (2 messages)

Next thread: Questions regarding startup of imsm container by Randy Terbush on Monday, March 22, 2010 - 8:56 pm. (20 messages)