[sheepdog] [PATCH V2 4/4] collie: introduce '-o, --oid' option to 'collie vdi read' command

[Yunkai Zhang]

On Thu, Aug 23, 2012 at 9:25 PM, MORITA Kazutaka
<morita.kazutaka at lab.ntt.co.jp> wrote:
> At Tue, 21 Aug 2012 22:09:43 +0800,
> Yunkai Zhang wrote:
>>
>> From: Yunkai Zhang <qiushu.zyk at taobao.com>
>>
>> V2:
>> - just do rebase
>> ----------------- >8
>>
>> This option is useful when we known the replicas of one object are different
>> (for example: we have checked it by executing 'collie vdi check' command), and
>> we want to export the specify replica of that object. It can help us to test
>> wich replica is correct.
>>
>> The format of this option is:
>> $ collie vdi read --oid oid at host:port[,oid2 at host2:port2]... <vdiname>
>
> What is the situation you want to specify the replica to be recovered?
> If replica inconsistency happens, reading either of replicas is okay
> from the point of view of block device semantic.

When inconsistency happens, in the worst case, we just need to make
replicas with the same value but needn't to care about which replica
is correct.

But in the best case, only several objects were polluted, then this
patch can give us a chance to verify them, This patch is used to work
with 'collie vdi check' command, that is my original intention when
developed it.


>
> Thanks,
>
> Kazutaka



-- 
Yunkai Zhang
Work at Taobao