Bad Sectors

[BostonDan]

Hi Everyone- I have a ST31000528AS hard drive in a Synology DS209 which is reporting bad sectors.
Day 1, 1 bad sector
Day 2, 2 bad sectors
Day 3, 3 bad sectors
Day 4, 5 bad sectors
Day 5, 7 bad sectors
Day 6, 8 bad sectors
I assumed that this is an indication the entire drive is failing and purchased a replacement. Prior to installing the replacement, I'm having second thoughts because this is such a small percentage of the drive, 8 sectors out 1,953,525,168.
Can anyone provide insight if this is an indication the entire drive is failing, or if this is likely to stop increasing
Thanks again,
Dan

 

[claykin]

Hi Everyone- I have a ST31000528AS hard drive in a Synology DS209 which is reporting bad sectors.
Day 1, 1 bad sector
Day 2, 2 bad sectors
Day 3, 3 bad sectors
Day 4, 5 bad sectors
Day 5, 7 bad sectors
Day 6, 8 bad sectors
I assumed that this is an indication the entire drive is failing and purchased a replacement. Prior to installing the replacement, I'm having second thoughts because this is such a small percentage of the drive, 8 sectors out 1,953,525,168.
Can anyone provide insight if this is an indication the entire drive is failing, or if this is likely to stop increasing
Thanks again,
Dan

I'm not familiar with how Synology reports SMART data. Can you post the SMART data that the Synology box has recorded? I'm guessing that the count you are reporting is what SMART calls reallocated sector count. In short, the answer is yes, if the count is increasing daily, the disk is slowly failing. The slow failing could at anytime turn into sudden failure or in some cases the disk could last for quite a while longer before it fails.

In any case I would make sure to remove it, run Seatools and see what Seatools reports. Unfortunately, Seagate (and other OEMs) don't like to replace disks so Seatools will often report a disk is OK when it has increasing problems. There's a threshold they program into Seatools for when it trips and gives you a failure message. I would still recommend the disk be replaced and you can easily do so. Seagate offers options to exchange a disk even when Seatools says its OK. Seagate is good about that if you know to ask the right questions.

Have you checked to make sure your 7200.12 disks have the CC46 firmware? http://seagate.custkb.com/seagate/crm/selfservice/search.jsp?DocId=213891

 

[BostonDan]

Actually a ReadyNAS-DUo

Thanks Claykin for responding once again.
I messed up my post when I made it. The hard drives are actually in a ReadyNAS-Duo. I also own a Synology DS209 and my brain was thinking of it as I was typing the post. The firmware I was running on both drives is CC38. I'll be updating the remaining good drive very soon and performing a surface scan as well using the tools from Seagate. Do you know what the firmware fixes? I couldn't find any information.

Because you asked, I've attached a screenshot showing the Synology DS209 SMART data (no problems with this NAS).

I replaced the faulty drive in the ReadyNAS when the Reallocated Sector Count exceeded 20, so I can't provide that screenshot of the faulty drive, but attached is a screenshot of the good Seagate 1TB drive in the ReadyNAS-Duo. With the exception of the Serial Number and the Reallocated Sector Count, the data matched exactly my second drive.

As I was reading about drive failures, there were some stating that the drive heads go out of alignment (reasoning why the bad sector count increases exponentially) and that by low-level formatting the drive, it would realign the entire drive and users could recover use of the entire drive. I'm not one to take risks, so I just bought a new drive. Any thoughts?

Thanks again,

Dan