[sheepdog-users] Single-node sheepdog for testing

[Hitoshi Mitake]

On Fri, Apr 18, 2014 at 12:01 PM, Scott Devoid <devoid at anl.gov> wrote:
> Thanks, that's what I suspected. I'll use the shutdown command from now on.
> :-)
>
> To your other question, I'm running the 0.6.0 version--I know, it's way out
> of date! But I am trying to get sheepdog integrated as an optional
> configuration for Devstack, and I don't think the Devstack team likes
> including alternate PPAs or building other projects from source. That's the
> version that Ubuntu 13.10 supports; hopefully Devstack will bump itself up
> to Trusty soon.

I see. There are differences between 0.6.0 and the latest versions. If
you meet troubles when you update sheepdog in the future, please see
CHANGELOG.md file or post the problems to this list :)

Thanks,
Hitoshi

>
> ~ Scott
>
>
> On Thu, Apr 17, 2014 at 9:41 PM, Hitoshi Mitake <mitake.hitoshi at gmail.com>
> wrote:
>>
>> On Fri, Apr 18, 2014 at 10:16 AM, Scott Devoid <devoid at anl.gov> wrote:
>> > Thanks Hitoshi,
>> >
>> > So I am seeing some interesting behavior when I try to shutdown and
>> > restart
>> > my 3 node cluster:
>> >
>> > $ for pid in `pgrep | sheep`; do kill -15 $pid; sleep 2; done
>> > $ for i in 0 1 2; do sheep -c local -d /path/to/store/$i -z $i -p 700$i;
>> > sleep 1; done
>> >
>> > Shutdown works fine, but when I go to start the cluster up the first
>> > member
>> > fails when the second joins. I think this is because the second member
>> > has a
>> > later epoch than the first.
>> >
>> > Here is the tail of the first member logs:
>> > http://paste.openstack.org/show/76195/
>> >
>> > Let me know if I am doing things incorrectly.
>>
>> A little bit follow up:
>>
>> As you say, the problem is caused by the difference of epoch numbers.
>>
>> The detail of the problem is like below:
>> 1. sheep A, B, and C form a cluster
>> 2. kill command kills A, and the killing is notified to B and C. So B
>> and C update their membership (called epoch).
>> 3. the for loop kills B and C with 2 seconds interval
>> 4. restart sheeps, the second for loop restarts A
>> 5. the for loop restarts B. B's membership is newer than A. So A exits
>> voluntary because it doesn't know the latest membership.
>>
>> Thanks,
>> Hitoshi
>
>