[sheepdog] [PATCH] sheep: exit when version of QEMU is old

[Liu Yuan]

On 02/28/2013 06:59 PM, Hitoshi Mitake wrote:
> I encountered a problem which might be caused by a combination of old
> QEMU and latest sheepdog. Suddenly qemu reported I/O errors and
> objects of sheeps seemed to be broken. In the log message, I could
> find the message "Some VDI faild to release the object cache. Probably
> you are running old QEMU." So I updated my QEMU and the problem seemed
> to be solved.
> 
> I'm not sure the real source of the problem was the version
> mismatch. But from a perspective of administration, I believe that
> sheep should exit in such a case.
> 
> This patch make sheep exits in such a case. Ideally, sheep should
> refuse connections from old QEMUs. This is an urgent solution.

We need support running old QEMU even with lessened functionality. We'd
better find the root cause instead of running away from it.

Thanks,
Yuan