hammer upgrade changes md5 checksum

[Michael Neumann]

Am Mon, 16 Mar 2009 19:06:51 -0700 (PDT)
schrieb Matthew Dillon <dillon at apollo.backplane.com>:

> :Hi,
> :
> :Now I upgrade the /slave:
> :
> :  hammer pfs-upgrade /slave
> :
> :and get a different checksum:
> :
> :  cd /slave
> :  tar cf - DIR | md5     # 3613c...
> :
> :If I downgrade again, I get the same checksum as before (9472f...).
> :
> :Hm, just curious why this happens and if this might be a bug?
> :
> :Regards,
> :
> :  Michael
> 
>     This is probably because HAMMER treats snapshots differently from
>     live.  The mtime and atime will be locked to the ctime when
> accessed from a snapshot.  tar does not record atime, but I'm pretty
> sure it does record mtime.

Ah, that's it! Thanks Mattew and Simon.

Regards,

  Michael