Hello Friends! Recently we’ve got a case where we saw the next message in utility terminal tab after drive’s power on:
最近我們接到一個(gè)希捷硬盤數(shù)據(jù)恢復(fù)案例，在打開硬盤電源啟動(dòng)后，我們看到了指令終端有如下信息：

MCMTFileHandler: EXCEPTION: Failed MCMT read request

We see such cases pretty often here in support, so let’s see what can be done to bypass this error and get the full drive’s ID and user data access.
我們經(jīng)常碰到這樣的情況，所以讓我們看看可以做些什么來(lái)繞過這個(gè)錯(cuò)誤，并獲得完整的硬盤ID和用戶數(shù)據(jù)區(qū)的訪問以完成此類故障的硬盤數(shù)據(jù)恢復(fù)工作。

As we know,?MC (MediaCache) – A temporary non-user addressable storage on magnetic media used to buffer incoming or outgoing data. If the drive works a lot, the MediaCache area can be written not correct, and the appropriate system file (vol.0x03 File ID 0x0346), related to the MediaCache, becomes unreadable. Let’s view that in?real drive.
正如我們所知道的，MC (MediaCache) –?磁介質(zhì)上用于緩沖輸入或輸出數(shù)據(jù)的臨時(shí)非用戶可尋址存儲(chǔ)器。如果驅(qū)動(dòng)器工作時(shí)間太長(zhǎng)，那么MediaCache區(qū)域會(huì)寫入錯(cuò)誤，以及相應(yīng)的系統(tǒng)文件 (vol.0x03 File ID 0x0346),與MediaCache相關(guān)，變得無(wú)法讀取。 讓我們看看真正的驅(qū)動(dòng)。

The drive ST500DM002 starts good, spinning without any bad sounds, but can not read the ID, and shows the next error in terminal:
ST500DM002啟動(dòng)是正常的，沒有任何異常的聲音，但是不能讀取ID，并在終端顯示下面的錯(cuò)誤信息：

If we try to check the 346 system file using the reading command, we can see the next output:
如果我們嘗試使用讀取命令來(lái)檢查346個(gè)系統(tǒng)文件,我們看到下面的輸出信息：

which means that 346 system file is readable. But the reading command (F3 T>r) is checking only ?a few sectors at the beginning of the system file, so we can not be sure if the whole system file is really good. So we need to check it manually using the reading thru the terminal. We go to Tools->Utility extensions->Service information objects:
這意味著346個(gè)系統(tǒng)文件是可讀的。但是讀取命令(F3 T>r)只檢查系統(tǒng)文件開頭的幾個(gè)扇區(qū),所以我們不能確定整個(gè)系統(tǒng)文件是否真的很好.所以我們需要手動(dòng)地使用讀取終端來(lái)檢查它.使用Tools->Utility extensions->Service information objects:

and then in System File?tab enter the File ID we want to check:

 

To make the reading faster we can increase the COM-port speed before:
為了使讀取速度更快，我們可以增加之前的接口速度:

As we can see at the next screenshot, the reading has stopped at block 129 from 321, and the system file was not read:
正如我們?cè)谙乱粋€(gè)截圖中看到的，讀取時(shí)已從321的第129塊停止，系統(tǒng)文件未被讀取:

Looks like we have found the problem: 346 sysfile, which is necessary for drive initialization, is bad, and we need to fix it to make the drive work. But what if system heads can not write in Service Area? We can check the writing by following the next manual.
看來(lái)我們發(fā)現(xiàn)了問題:346系統(tǒng)文件,這是驅(qū)動(dòng)初始化的必要條件，我們需要修復(fù)它以使驅(qū)動(dòng)器正常工作,但是如果系統(tǒng)磁頭不能寫入服務(wù)區(qū)呢？我們可以按照下一個(gè)文檔來(lái)檢查寫入。

So, we have checked that both system heads can write good, and now we can try to fix the bad sysfile. The good news is we can use the same system file from the same drive family donor. The bad news is the damaged system file can be unreadable because of physical bad sector in SA, and in this case there is nothing can be done to get the drive to work.

Let’s try to write the 346 system file from another Pharaoh drive. I filled it with 00 before to make the drive initializing faster.
讓我們?cè)囍鴮懭肓硪粋€(gè)希捷Pharaoh家族硬盤上346系統(tǒng)文件，我把它填滿了00，以使驅(qū)動(dòng)器的初始化速度更快。

It’s always good to have the resource backups in stock. If you have no compatible backups yet, you can download the 346 for Pharaoh?and?Grenada?by pressing the links.
有好的資源備份。如果你還沒有兼容的備份，你可以在這個(gè)下載r Pharaoh 和 Grenada 家族的346文件。

To write the donor’s sysfile we press the Load button:

Then select and write the donor’s system file using the Write data to HDD button:

When the writing ends, we refresh the 346 sysfile and see that we were lucky and there are no bad sectors in sysfile’s body, and 346 has been written good and can be readable again.

So we restart the drive, wait for readiness, and get the full ID and sector access!
因此，我們重新啟動(dòng)驅(qū)動(dòng)器，等待就緒，并獲得完整的ID和正常訪問扇區(qū)！