unraid smart check – dead WD green drive

errors on unraid GUI – sometimes its a loose cable, sometimes its an issue with the drive.

Run this command to check smart status

smartctl -a -d ata /dev/sda
or if you are using a newer SATA controller
smartctl -a -A /dev/sda


unfortunately in my case, looks like drive is pretty much dead… not too bad for a drive almost 5 years old.

its pretty typical of a WD green drive in its default config to die in this type of environment, no plans to replace it with a similar type drive. You can see below the incredibly high LCC count which indicates the drive header has parked this many times over its life. This is probably part of the problem – there is a tool you can run (check this vid, link for  WDIDDLE3 also in comments – http://www.youtube.com/watch?v=J2eYyRI_F98) which disables the intellipark feature of the green drive. I never disabled the park timeout before this drive died (which defaults to 8 seconds!) — note: i have disabled it completely on my other green drives.


Model Family: Western Digital Caviar Green
Device Model: WDC WD10EADS-00M2B0
Serial Number: WD-WCAV51020991
LU WWN Device Id: 5 0014ee 2588170a5
Firmware Version: 01.00A01
User Capacity: 1,000,204,886,016 bytes [1.00 TB]
Sector Size: 512 bytes logical/physical
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA8-ACS (minor revision not indicated)
SATA Version is: SATA 2.6, 3.0 Gb/s
Local Time is: Thu Oct 30 18:48:41 2014 NZDT
SMART support is: Available – device has SMART capability.
SMART support is: Enabled

SMART overall-health self-assessment test result: FAILED!
Drive failure expected in less than 24 hours. SAVE ALL DATA.
See vendor-specific Attribute list for failed Attributes.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
1 Raw_Read_Error_Rate 0x002f 168 154 051 Pre-fail Always – 12560032
3 Spin_Up_Time 0x0027 149 105 021 Pre-fail Always – 5508
4 Start_Stop_Count 0x0032 099 099 000 Old_age Always – 1253
5 Reallocated_Sector_Ct 0x0033 119 119 140 Pre-fail Always FAILING_NOW 648
7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always – 0
9 Power_On_Hours 0x0032 041 041 000 Old_age Always – 43079
10 Spin_Retry_Count 0x0032 100 100 000 Old_age Always – 0
11 Calibration_Retry_Count 0x0032 100 100 000 Old_age Always – 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always – 371
192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always – 363
193 Load_Cycle_Count 0x0032 001 001 000 Old_age Always – 1932037
194 Temperature_Celsius 0x0022 118 076 000 Old_age Always – 29
196 Reallocated_Event_Count 0x0032 001 001 000 Old_age Always – 463
197 Current_Pending_Sector 0x0032 199 193 000 Old_age Always – 323
198 Offline_Uncorrectable 0x0030 199 190 000 Old_age Offline – 186
199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always – 0
200 Multi_Zone_Error_Rate 0x0008 003 001 000 Old_age Offline – 39455

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Short offline Completed: read failure 90% 24914 789707146

Here is a good post on another forum about the issue (which also seems to hit some of the new RED drives);


I have disabled intellipark on the rest of my green drives (since they are close to 5 years and probably near failure). I have some new RED drives which i have increased the time out to 300 seconds. (most come with 300 sec timeout, but older firmware is at 8 seconds). From what I’ve been reading there is no physical difference between WD red and green drives, only the firmware differs. So if you are going to put some green drives into a NAS / RAID or Server environment ensure you run wdidle3 and either disable or change timeout on intellipark to 300 seconds. (then its pretty close to a red drive)

To check current status

wdidle3 /r

to disable intellipark

wdidle3 /d

to set to 300 (max) timeout

wdidle3 /s300

4k sector hard drives and zfs

I hit this as a problem recently. One of my disks died in my raidz so i ran down to the store and grabbed me a replacement WD10EARS (Western Digital 1Tb Green) drive.


The one thing the store didn’t mention to me is the new 4K cluster sizing on the drive. I guess they assume most people run windows (though the issues are also present in XP). See these posts…


Unfortunately they really don’t work as well as you’d like in a server :(

  • They come with a 5 second head spin down setting that causes them to park their heads if they have been left idle for more than 5 seconds. As it takes a second or two to spin back up this can result in a very laggy experience during interactive sessions.
  • They do not have NCQ or any form of command queing/optimisation. This means that (on FreeBSD at least) you are stuck in the LOOK elevator. In particular this was noticed when doing sequential read & write (think dump|restore tar|untar etc) and interactive tasks simultaneously
  • They really suck with FreeBSD and ZFS…


While the other 512-byte sector HDDs were reading/writing at 30MB/s sustained, this EARS model did not exceeded the 1MB/s barrier.

I know for sure that this is related to the 512-byte sector firmware emulation, because the disk works perfectly well if I partition it in a 4k-sector alignment.

The thing is that even in that way, using it in a ZFS RAIDZ configuration the performance is very poor because RAIDZ uses a dynamic stripe size.

The bottom line here is that folks like me, that use different versions of Unix, need the firmware to present the disk as a 4K-sector disk to unleash the full potential of the technology. The OS is already prepared to support that sector size, no need for emulation here.


Some preliminary testing that I have done…the WD20EARS (2TB advanced format drives) actually presents emulated 512byte sectors to the host o/s.

The drive documentation indicates that jumpers 7-8 should be enabled if the o/s does not support advanced format drives – the drive still present 512 bytes sectors.

I have attempted to raise a support ticket querying this, and how one can disable 512byte sector emulation in the drive (perhaps through a firmware upgrade) but I have not received any response to date.

Hopefully is enough people raise support tickets, WD may release firmware that allows the drive to natively present 4k blocks. Other doco indicates several other jumper combinations – all do not seem to make the drive present 4k byte blocks.

Perhaps someone internal to sun that has a relationship with WD may be able to shed some light on this? It would be fantastic to find out that I was just doing something wrong -> then I can get the drives to be seen on 32bit systems (ie – our embedded kit for osol, velitium)

Tested using b133 (64bit intel).

Try to avoid the green drives in ZFS for now. Remember to do your research before you buy a bunch of disks. I was caught off guard by this small change (works fine in win7 etc) which kills performance in ZFS. Ouch.