Solutions to Seagate Sector Access Interruption (Part Two)

Video download link：https://us.mrtlab.com/video/sgtsectinter.rar

In Solutions to Seagate Sector Access Interruption (Part One), we've demonstrated how to manually make a sector access interruption by modifying entries in defect lists, confirming specific reasons which can cause sector access interruption. So in practical work, when we encounter a Seagate hard disk with sector access interruption, how should we analyse and solve the problem?

Frequently-used MRT Three-step strategy is a universal standard repair method to deal with Seagate sector access interruption problem. But after knowing the principle and specific reasons, we can try to manually repair this malfunction.

Here, let's introduce a new MRT Three-step strategy, and main operation processes are listed as follows:

1. Locate the LBA address of the bad point, then query its PBA address

We need to locate the LBA address of the bad point to the size of one block in logical scan, after get the specific LBA address, we can use "Track sector address converter" to get the PBA address of this bad point. We can input both decimal value and hexadecimal value in the box of LBA address in "Track sector address converter", and if we want to input value in hexadecimal, we need to add 0x before the value as a prefix. In Solutions to Seagate Sector Access Interruption (Part One), because we did this operation in terminal condition, and in terminal condition, only hexadecimal value is supported, so we had to convert LBA address into hexadecimal value that time.

2. Check whether we can find an entry with same address of the bad point's PBA address in V40 list or an entry with nearby address in V100 list.

After get the specific PBA address of the bad point, we need to have a check in nonresident G-list and P list, to see whether we can find an entry with same address of the bad point's PBA address in nonresident G-list or whether we can find an entry with nearby address in P list.

3. According to the hit situation to find the relevant defect list, and analyse the real reason of this sector access interruption.

If there is such an entry in V40 list, whose PBA address is just the same with the PBA address of the bad point, then we can say this entry might cause the bad point with a large probability. Thus we can try to delete this entry in V40 list, and see if this bad point can be fixed or not. Scan again, if the bad point can be normally read out, then it means we've successfully fixed the bad point, and it can prove redundant entries in V40 list is the reason that caused this sector access interruption. In such condition, we can fix it by deleting those wrong extra entries and recalculating translator.

Demo video link of how to delete redundant entries in V40 list to repair sector access interruption problem: https://us.mrtlab.com/video/sgtsectinter.rar

If we can not find such an entry in V40 list, then we need to have a check in P list(V100 list), to see whether there is an entry that matches or comes near to the PBA address of the bad point. If there is such an entry, then we can say this entry might cause the bad point with a large probability, and we need to use its information in V100 list to find and delete the corresponding entry in V10 list, and see whether the bad point can be fixed. When finding corresponding entry in V10 list, we only need to match the head number and the value of logical cylinder. If there are several entries sharing a same head number and logical cylinder value, then we need to use SFI address to distinguish. Scan again, if the bad point can be normally read out, then it means we've successfully fixed the bad point, and it can prove redundant entries in V10 list is the reason that caused this sector access interruption. In such condition, we can also fix it by deleting wrong extra entries and recalculating translator.

Demo video link of how to delete redundant entries in V10 list to repair sector access interruption problem: https://us.mrtlab.com/video/sgtsectinter.rar

If we can not find an entry with same address of the bad point's PBA address in V40 list or an entry with nearby address in V100 list(comes near refers to gap difference within a few sectors, if the gap difference is large, it can not be called as a nearby address), then generally it is not redundant entries that caused this sector access interruption. So in this situation, we should consider to add defect entries instead of deleting.

We open translator recovery, input bad point's address, add some defect to it and wait for the process to be done. It should be noted that, when using translator recovery, we must pay attention to the option of 4K and non 4K, for 4K hard drive, please do not forget to select the option of using scanning feature (support 4K tech).

When using translator recovery to add defects, it will add bad point's PBA to V40 list as well as adding its defect length. If the process can not be finished for a long time, we would like to suggest to stop it and have a check in V40 list, to see whether the defect has been added it or not. If it has been added to V40 successfully, then there should be an entry which hits the PBA address of the bad point while its length is the length of circulatory; and if there is no such an entry, that means defect had not been added to V40 yet, and at that time, we need to find the reason why we could not add defect to V40 list. Closed SMART subsystem is one possible reason(it should be opened), and there are other possible reasons, such as damaged firmware, and we can not add defect to V40 successfully when translator recalculation can not be executed. And in this situation, we should fix this problem first, only when we can add defect to V40 list do we have the access to fix sector access interruption problem.