Filesystem creation with integrated bad-block detection

[Lowell Gilbert]

Pásztor Richárd <ricsip at mailbox.hu> writes:

> I wonder if it would be possible to implement under freeebsd an
> interesting feature
> which can be found in linux:
> 
> mkfs.ext2(8)
> .......
> -c
> Check the device for bad blocks before creating the file system. If
> this option is specified twice, then a slower, destructive, read-write
> test is used instead of a fast read-only test.
> ...

FreeBSD has some tools in this area (see, for example, badsect(8)),
but they have largely atrophied.

> I searched the archive for this subject, and i found that simple
> answer that modern hard drives have
> the so called spare sectors, and if they cant do these reallocations
> transparently because they
> ran out of those reserved sectors -> throw the drive into the trash.
> But what abou using freebsd on older machines with hard drives that
> dont support spare sectors?
> Having a few bad sectors doesnt mean that a 4-5 Gb driver is useless
> because one isnt able to mark those
> few sectors.

If the disk is multiple gigabytes, then it's unlikely to be old enough
to lack spare sector support.  IDE has been standard for a *long* time
now, and from my experience, pretty much *every* IDE drive *ever* has
come with block remapping turned on by default.

See the FAQ entry on the subject:
 What do I do when I have bad blocks on my hard drive?
 http://www.freebsd.org/doc/en_US.ISO8859-1/books/faq/troubleshoot.html#AWRE