Dangerously dedicated mode with FreeBSD 10.1

[Warren Block]

On Fri, 21 Nov 2014, Nathan Whitehorn wrote:

>> This might be an "Advanced Format" thing, where the drive uses 4K sectors 
>> but reports that it uses 512-byte sectors.  The forum thread shows that it 
>> does not align to 4K on SSDs.  My SSDs also report 4K stripesize but only 
>> 512 byte sectoresize.
>> 
>
> Sure, but the installer aligns to the reported "stripe size". For AF disks 
> like your SSD, the kernel reports the right thing in the stripe size.
>
> Where in the forum thread does it show an issue? The only thing I see is some 
> gpart output from a 10K spinning SAS disk, which almost certainly has 
> 512-byte physical sectors.

Hmm, I thought that was still about an SSD.  I sent a followup asking 
for the block size of the drive.

I set out to test this on a machine with an SSD, but can't get an 
install image to work from my PXE setup (it can't find the install disk 
label), and have no easily-accessible DVD drives or empty memory sticks 
right now.  It seems like it should be easier than this.

Anyway, for now let's say it works.