[gPXE] Fw: Fw: Fw: Booting MS-DOS using gPXE/iSCSI: C: drive is readonly

[Jonathan Andrews]

On Thu, 2010-03-25 at 23:10 +0100, ACS wrote:
> "Shao Miller" wrote
> > Good day Adrian,
> 
> > So is it possible that your SAN's underlying storage device/file is 
> > read-only?
> No.
> Without "verify on" command, I can alter txt file fine, changes
survive 
> MS-DOS reboot, so there's no caching that fools me
> With verify on I end up with  zero byte 2.txt file,  after typing
command 
> echo 1 > 2.txt
> 
> at the moment, my "SAN" is a linux host running vbladed for AoE
target.
> At topic start, I was using iSCSI target using ietd
> 
> Is anyone able to re-create this problem?
> Is it some race condition, where the sector verify-read operation is
started 
> before sector write is finished?

Just a blind stab but you could try mounting the linux filesystem as
"sync" rather than "async".  DOS requires a read before write with
verify on, perhaps linux does not give the correct answers without a
flush before read ?

Pure guess mind .....

Jon