从软盘硬盘驱动器中提取扇区

No one likes to think about a hard-drive going bad much less experiencing trouble with one, but how do hard-drive diagnostic tools actually know if sectors are bad or not? Today’s SuperUser Q&A post has the answers to a curious reader’s questions.

没有人喜欢想到硬盘坏了，而很少遇到麻烦，但是硬盘诊断工具实际上如何知道扇区是否坏呢？ 今天的“超级用户问答”帖子回答了好奇的读者的问题。

Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites.

今天的“问答”环节由SuperUser提供，它是Stack Exchange的一个分支，该社区是由社区驱动的Q＆A网站分组。

Photo courtesy of Matthew (Flickr).

照片由Matthew(Flickr)提供 。

问题 (The Question)

SuperUser reader David wants to know how hard-drive diagnostic tools know if a sector is bad:

超级用户读者David想知道硬盘诊断工具如何知道一个扇区是否坏：

When I run across a hard-drive that may be failing, I scan it using ViVARD, which reliably lets me know if the hard-drive needs replacing or not. How do these sorts of tools work? How can they tell a bad sector from a good sector?

当我在可能发生故障的硬盘驱动器上运行时，我使用ViVARD对其进行了扫描，它可以可靠地让我知道该硬盘驱动器是否需要更换。 这些工具如何工作？ 他们如何分辨一个好的部门和一个坏的部门？

How do hard-drive diagnostic tools know if a sector is bad or not?

硬盘诊断工具如何知道某个扇区是否损坏？

答案 (The Answer)

SuperUser contributors Stavr00 and Ole Tange have the answer for us. First up, Stavr00:

超级用户贡献者Stavr00和Ole Tange为我们找到了答案。 首先，Stavr00：

Modern hard-drives implement a system in firmware called S.M.A.R.T. which collects statistics on the hard-drive’s performance and automatically avoids data loss by moving data away from bad sectors.

现代硬盘驱动器在名为SMART的固件中实现了一个系统，该系统收集有关硬盘驱动器性能的统计信息，并通过将数据移出不良扇区来自动避免数据丢失。

Diagnostic tools query the hard-drive’s S.M.A.R.T. software in order to build a health check report. Bad sectors are detected upon accessing the hard-drive, avoided, and necessary relocation is done by the S.M.A.R.T. system.

诊断工具查询硬盘驱动器的SMART软件，以生成运行状况检查报告。 在访问硬盘驱动器时会检测到坏扇区，这可以避免，并且SMART系统可以完成必要的重定位。

Followed by the answer from Ole Tange:

随后是Ole Tange的回答：

I am not familiar with ViVARD, so this is a general answer.

我不熟悉ViVARD，所以这是一个一般性的答案。

S.M.A.R.T.

聪明

S.M.A.R.T. is a part of most modern hard-drives. It registers when the hard-drive sees a bad sector and when the ‘seek or spin up time’ is longer than normal. These are all indicators that a hard-drive is failing.

SMART是大多数现代硬盘驱动器的一部分。 当硬盘驱动器看到坏扇区并且“搜索或加速时间”长于正常时间时，它将注册。 这些都是硬盘驱动器发生故障的指示灯。

The way the hard-drive salvages a failing sector is due to error correcting codes (usually Reed-Solomon) that can perform a rescue if a few bits are wrong. If many bits are wrong, then the hard-drive tries salvaging by reading the sector over and over again. When it finally gets it right, it saves it to one of the spare sectors.

硬盘挽救故障扇区的方式是由于纠错码(通常是Reed-Solomon)引起的，如果有几处错误，它们可以执行救援。 如果很多位错误，则硬盘驱动器尝试通过一次又一次地读取扇区来进行补救。 最终使其正确时，将其保存到备用扇区之一。

Reading Sectors

阅读领域

The hard-drive reallocates sectors with read errors to a set of spare sectors that are reserved for this. The operating system does not usually see this, but sees the whole hard-drive as having no errors. Only when there are no more sectors to reallocate to (or the sector cannot be salvaged) will the operating system see the broken sectors.

硬盘驱动器将具有读取错误的扇区重新分配给为此保留的一组备用扇区。 操作系统通常不会看到此错误，但会认为整个硬盘驱动器没有错误。 仅当没有更多扇区要重新分配(或无法挽救该扇区)时，操作系统才会看到损坏的扇区。

But it is possible to bypass error correction. I believe it is different for each model, but maybe ViVARD does it? This way you can read the actual data on the hard-drive. By reading this you will be able to see which sectors have errors, even if the operating system itself sees no errors.

但是可以绕过纠错。 我相信每种型号都不同，但是也许ViVARD可以吗？ 这样，您可以读取硬盘驱动器上的实际数据。 通过阅读此内容，即使操作系统本身未发现任何错误，您也可以查看哪些扇区有错误。

Have something to add to the explanation? Sound off in the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.

有什么补充说明吗？ 在评论中听起来不错。 是否想从其他精通Stack Exchange的用户那里获得更多答案？ 在此处查看完整的讨论线程 。

翻译自: https://www.howtogeek.com/230492/how-do-hard-drive-diagnostic-tools-know-if-a-sector-is-bad-or-not/

从软盘硬盘驱动器中提取扇区