How much unallocated space to leave around a bad sector?

I have a very old 1 TB hard drive with one bad sector. Using the "Surface Test" option in Macrorit Partition Expert v8.1.0 I have narrowed down its location down to the exact Megabyte (it's at at 887.288 MB of 953.867 MB).




chkdsk /F didn't even find that bad sector.

It's probably a physical fault too*, though not one that has had a chance to cause any problems yet.

(Yeah, I know. Bad sectors are, err, bad. I only intend to use the drive as backup, and probably for files that don't change very often, either... at least not for now. But a backup of those files *should* exist, and currently doesn't yet.)

Definitely don't wanna aggravate that bad sector though, hence I'm using Macrorit Partition Expert to "split" the disk, and leaving some room around the bad sector. Everything currently on the drive is already moved elsewhere and can be deleted from here.

My question is simply: How much space should I / do I have to leave unallocated around the bad sector? 100 MB in either direction? 1 GB?

Like I said, I know it's exact location.






^{*The only reason I initially investigated the drive was because of CrystalDiskInfo reporting about 11 (in decimal) Current Pending Sectors - and the number got a little larger (first 15, then 17 [in decimal]) simply from "rightclick->properties" on a specific directory on the drive.
Got all my data out, only one unimportant file failed to copy. Even verified the backup was correct with Synchredible Backup's "compare file content" option, which surprisingly did not negatively affect the Current Pending Sector Count. I'd left the drive alone for the last few years, but I've run low on space atm so I came back around to it.}

Consider running chkdsk /b /v from a bootable flash drive.

Code:

/b	
Use with NTFS only. 
Clears the list of bad clusters on the volume and rescans all allocated and free clusters for errors. 
/b includes the functionality of /r. 
Use this parameter after imaging a volume to a new hard disk drive.

https://learn.microsoft.com/en-us/wi...s=event-viewer

I totally agree with both Dalchina & Jumanji.

dalchina

"1 bad sector on the whole disk surface should have no effect whatsoever. "

-- manufacturers always leave a bunch of space to use in the case of bad sectors developing; this is normal and keeps our data safe

jumanji

"This idea is simply not practical and maintainable. Throw it into the dust bin."

--#1 IF there is an actual hardware issue, you will experience this also. However, are you IT knowledgeable enough to keep track of it and to preserve your data BEFORE loss can occur?

SO, although I know that bad sectors are a normal part of storage devices by their nature, I also do not want to loose any of my data.
That being said, if one of my backup drives starts to act up, I replace it immediately and use the suspected faulty drive for non-critical work. I might install some non-critical apps on it for example or I might use it solely as a "temp folder" or "scratch disk" drive. I might just toss it if I decide it's not worth it to take any chances.

Storage space is fairly cheap most of the time.

Also, I have seen brand new, top end drives fail out fo the box, within a couple days/weeks/months - we need to be aware of this to.

SO, my BEST advice, is to ditch that drive and purchase 2 (or more) drives to replace it.
Duplicate the backup so each drive is mirrored and have exactly the same data stored on them.

If one gets pooched your data is safe. Replace the failing drive. Migrate your data to it, resume 2 back up drive system.

I personally have 4 drives storing my personal/work data. SO, 3 of them could fail right now and I could still recover.
2 of them are located on my server - backup daily, 1 of them is in a docking station - I back up to this one once per month - 1 is in my main desktop.

I have lost all my data before - it's a bitch - so no more.

Have fun