銳銨也不建議用WD Desktop
http://www.savemore.com.tw/news_con...=580&modal=true

適用品牌 / 產品型號

RAIDON / STARDOM 全系列產品線

一、通報內容說明
根據銳銨(RAIDON) & WD 官方網站訊息顯示，當WD Desktop 系列硬碟有錯誤時，硬碟便會進入deep recovery cycle 模式，並進行為時2 分鐘的修復動作，但一般磁碟陣列控制卡允許的修復時間僅為7~15 秒，因此當硬碟沒有回應時，便將硬碟視為故障，而無法正常使用，故WD 不建議使用WD Desktop 系列硬碟於磁碟陣列環境之下。

另一方面，WD RAID 系列硬碟擁有TLER (Time Limited Error Recovery) 的特性，可以控制硬碟修復錯誤的時間於7 秒之內，以避免上述情況發生。

更多相關資訊，請參考銳銨科技官方網站www.RAIDON.com.tw，
及WD官方網站http://wdc.custhelp.com/cgi-bin/wdc..._accessibilityU


此頁內容原文摘錄如下：

Western Digital manufactures desktop edition hard drives and RAID Edition hard drives. Each type of hard drive is designed to work specifically as a stand-alone drive, or in a multi-drive RAID environment.

If you install and use a desktop edition hard drive connected to a RAID controller, the drive may not work correctly. This is caused by the normal error recovery procedure that a desktop edition hard drive uses.

Note: There are a few cases where the manufacturer of the RAID controller have designed their drives to work with specific model Desktop drives. If this is the case you would need to contact the manufacturer of that enclosure for any support on that drive while it is used in a RAID environment.

When an error is found on a desktop edition hard drive, the drive will enter into a deep recovery cycle to attempt to repair the error, recover the data from the problematic area, and then reallocate a dedicated area to replace the problematic area. This process can take up to 2 minutes depending on the severity of the issue. Most RAID controllers allow a very short amount of time for a hard drive to recover from an error. If a hard drive takes too long to complete this process, the drive will be dropped from the RAID array. Most RAID controllers allow from 7 to 15 seconds for error recovery before dropping a hard drive from an array. Western Digital does not recommend installing desktop edition hard drives in an enterprise environment (on a RAID controller).

Western Digital RAID edition hard drives have a feature called TLER (Time Limited Error Recovery) which stops the hard drive from entering into a deep recovery cycle. The hard drive will only spend 7 seconds to attempt to recover. This means that the hard drive will not be dropped from a RAID array. While TLER is designed for RAID environments, a drive with TLER enabled will work with no performance decrease when used in non-RAID environments.