Data recovery from HDD Seagate with the pending bug firmware

Seagate-Maxtor STM3250310AS storage vol. 250 gigabytes with SATA interface was brought for data recovery. The case was quite usual so I did not want to put it into my News column. The customer asked to give out some kind of conclusion about the disk problem and whose fault it might be.

My position when answering such questions in brief is as follows: "With rare exception the Failure reason of the storage (and in general of any hardware) cannot be named unequivocally". In that case the picture was more or less clear, as such a malfunction was a typical one for Seagate and STM 7200.8 - 7200.10 HDD.

The storage disc was defined in BIOS, but at attempt to load operational system, no matter from it, or faulty HDD was connected to the second channel, the computer buzzed.

It is necessary to note, that in was just a demonstration of "the microprogram features" of Seagate hard discs. The manufacturer position on notorious discs of series 11 was as follows:

"contains new ... feature.

This feature is defined approximately so: " Blocking of the user data access, at detection of threat of their full loss because of a various malfunctions arisen in HDD or degradation of the disc's magnetic layer" It Is done with the purpose to protect the data final loss and from their expensive recovery ...

Conditionally speaking, the microprogram itself is absolutely serviceable ... therefore it is rather difficult to recognize this feature as a vendor mistake..."

That's it. It is difficult for Seagate to recognize it as a mistake so they present it more likely as an advantage. In the manufacturer opinion, it is a powerful advantage. Earlier models of Seagate and Seagate-Maxtor HDD had another "useful feature". It had the same signs as I described in the beginning, and the faulty hard disk displays such messages at the technological port.

Error log of Seagate HDD
Error log of Seagate HDD

What happens in such a case? The matter is that owing to mr-elements properties deterioration of reading/recording heads, or because of design microdeformations due to thermal expansion during long run, the head start to read the user indefinitely.

Access time to the user area sectors turns out overestimated and so-called offline scanning, which watches "disc health" in a background mode, incurs all priority on request processing. It results in the signal "busy" on the interface, and the disc either stops reading, or reads extremely slowly. This line:

CE Log ErrCode=37 LBA=1e7dfe0 Type=5 Add To Pending 1e7dfe0

shows, that the disc has found a bad sector which though is read, but not so fast, as desirable. And this sector is subject to entering in candidate or, in another way, a pending list. I.e. It is not a bad block yet, but can become bad, and at the moment it is considered as "pending".

For such a disc repair it is necessary to start on factory self-testing cycle which arranges a signal level on the magnetic head assembly and recounts the adaptive - tuning information for the user zone. For data recovery it is necessary to make manually changes to the part of HDD microprogram which purges this "useful feature of firmware " and only then there is an opportunity to copy the data on serviceable HDD.