ext4 error messages

[Chris Murphy]

On Aug 26, 2014, at 9:24 PM, jd1008 <jd1008 at gmail.com> wrote:

> 
> On 08/26/2014 08:44 PM, Chris Murphy wrote:
>> On Aug 23, 2014, at 6:54 PM, jd1008 <jd1008 at gmail.com> wrote:
>> 
>>> So, it is not clear to me why there are all these errors, especially since ext4 is supposed
>>> to, by design, protect metadata's integrity in the face of such HW problems (which I
>>> am unsure what those HW problems are).
>> Well, no filesystem is impervious to hardware problems. Even if you have metadata and journal checksumming enabled, which isn't a default still, there is no guarantee.
>> 
>> Gist is, simple mount option -o journal_checksum for journal checksumming. For full metadata checksumming you need e2fsprogs 1.43. Current in F21 is 1.42.11-2, and it doesn't support mkfs.ext4 -O metadata_csum,64bit.
>> 
>> https://ext4.wiki.kernel.org/index.php/Ext4_Metadata_Checksums
>> 
>> 
>> Chris Murphy
> Well, that's a shame!
> At least after I had done the fsck, I lost no files as lost+found was empty.
> But that does not mean I did not lose file data in dirty buffers.

Well, files can be lost but not found, in which case they won't be in lost+found.


Chris Murphy