From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjammin2068 <benjammin2068@gmail.com>
Subject: Re: Best tool to partition Drives with new sector geometry - (WAS:
 Need Help with crashed RAID5 (that was rebuilding and then had SATA error on
 another drive))
Date: Sun, 18 Sep 2016 13:08:25 -0500
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As an update to this, here's some data:


the older Samsung HD103SJ drives (3 of the 4 drive RAID5 are still alive and well in this stack) have partition#1 (/dev/sdX1) which lists out at:

> [root@quantum myth]# sfdisk -l -uM /dev/sdc        <-- this is the output from one of the 3 HD103SJ drives. The partition was originally created by palimpest.
>
> Disk /dev/sdc: 121601 cylinders, 255 heads, 63 sectors/track
> Units = mebibytes of 1048576 bytes, blocks of 1024 bytes, counting from 0
>
>    Device Boot Start   End    MiB    #blocks   Id  System
> /dev/sdc1         0+ 953867- 953868- 976760001   fd  Linux raid autodetect
> /dev/sdc2         0      -      0          0    0  Empty
> /dev/sdc3         0      -      0          0    0  Empty
> /dev/sdc4         0      -      0          0    0  Empty

When I do the math:

976,760,001 * 1024  = 1,000,202,241,024 bytes --- ok, so that's /dev/sdX1

Now we take 1,000,202,241,024 / 4096 (block size of new drives) = 244190000.25 -- so I have a 1024byte (2 512byte sector) difference between the 2 models when trying to switch over.

Is there a best practice for how to contend with this? (resize the partition somehow on the raid and then alter the partitions sizes -2 sectors to make then /8 nicely? I know. Sounds insane. I have backups. I'd do it. :P )

Should I just eat the performance hit for now?

Thanks,

 -Ben