On Thu, Apr 5, 2012 at 2:03 PM, Michael Mol <mike...@gmail.com> wrote: > On Thu, Apr 5, 2012 at 2:50 PM, Canek Peláez Valdés <can...@gmail.com> wrote: >> On Thu, Apr 5, 2012 at 1:32 PM, Joost Roeleveld <jo...@antarean.org> wrote: >>> On Thursday, April 05, 2012 01:10:46 PM Canek Peláez Valdés wrote: >>>> On Thu, Apr 5, 2012 at 2:47 AM, 张春江 <zhangchunjian...@126.com> wrote: >>>> 2. GRUB cannot read ext4 partitions (GRUB2 can), so you are reading >>>> them as ext3 (I don't know if this can cause any problems). The reason >>>> I started to use GRUB2 was because I wanted to use ext4 for my /. >>> >>> I don't think ext4 and ext3 use the same disk layout, eg. I don't think that >>> can work. >> >> ext4 is fully backwards compatible with ext3, obviously; otherwise 张春江 >> would not be able to boot his system. > > Not exactly. If you use them, ext4 adds structures and features which > means the filesystem isn't liked by ext3-only code. I don't remember > which these are, I just know I tended to accidentally enable them > while tweaking filesystems with tune2fs.
tune2fs -O extents,uninit_bg,dir_index which, again, obviously 张春江 hasn't set, otherwise either he wouldn't be able to boot his system, or we had seen the warnings in his logs. Just as long as he doesn't use those new features, ext4 is fully backwards compatible with ext3. Regards. -- Canek Peláez Valdés Posgrado en Ciencia e Ingeniería de la Computación Universidad Nacional Autónoma de México
