[Pacemaker] [ANNOUNCE] The Booth Cluster Ticket Manager - part of multi-site support in pacemaker

[李泰勲]

Hi Jiaju

(2012/02/08 18:33), Jiaju Zhang wrote:
> On Wed, 2012-02-08 at 17:05 +0900, 李泰勲 wrote:
>> Hi Jiaju
>>
>> Thank you for your reply.
>>
>>
>> (2012/02/08 15:11), Jiaju Zhang wrote:
>>> On Tue, 2012-02-07 at 11:09 +0900, 李泰勲 wrote:
>>>> Hi Jiaju
>>>>
>>>> I am testing about working of booth while investigating booth source code.
>>>>
>>>> I don't understand ticket grant and revoke process perfectly that is 
>>>> related to connecting each booth
>>>> so I would like to know booth's working that would be matching your 
>>>> offering source code.
>>>>
>>>> Could you give me information about booth sequences that would be the 
>>>> ticket's grant,revoke,lease logic and working of ticket's expiry time.
>>> General speaking, you would want to grant some ticket on certain site
>>> initially, which means the corresponding resources can be run at that
>>> site. For the lease logic, ticket granting means that site has the
>>> ticket lease. The lease has an expiry time, after the expiry time, that
>>> lease is expired and the corresponding resources can't be run at that
>>> site any longer.
>>> If the site which has the original ticket granting is alive, it will
>>> renew the lease before the ticket expired, but if that site is broken,
>>> when the lease is expired, the lease logic will go into election stage
>>> and a new site will get the ticket lease, thus the resources will be
>>> able to run at the new site.  
>>> You can revoke the ticket from the site as well, but in most cases, you
>>> may not want to do this. The possible scenario I can think of is when
>>> the admin wants to do some maintenance work, or wants to do the ticket
>>> management manually.
>> We have understood booth working as your reply.
>> but I am wondering booth working process when it occurred splitbrain in
>> each sites.
>>
>> for example.
>>
>> siteA has ticketA grant.
>> siteB has no grant.
>> siteB is Arbitrator.
I mistook siteB is not Arbitrator. it's a siteC. sorry.

> Well, site B could not be the arbitrator. Arbitrator doesn't need to be
> a cluster site, it can be just a machine, but it should be in the 3rd
> site;)
>
>> if siteA connection fails and isolated from each sites,
>> automatically failover to siteB.
>> but ticketA did not revoke in siteA.
> The ticketA will expire in site A and then it will be revoked. The
> algorithm is able to guarantee before the ticket is granted to siteB, it
> has been revoked on siteA.
> However, current code has some bug on the ticket revoking;) I have an
> unfinished patch in hand and plan to submit it this week.  
All right. I will be waiting for it.
>
>> I think that ticket granting is alive in siteB and revoking in siteA.
>> Is that right that I think?
>>>> when do you think the booth's working is fixed and completed ?
>>> Oh, I have not finished it yet;) But I'm still working on it, since I
>>> also have some other tasks, maybe the progress is not fast these days;)
>>>
>>>> Is there anything to help you about booth's implementation or etc?
>>> The framework is finished, but there are still some bugs in it, so the
>>> code may not work for you for the time being, I'll be more than happy if
>>> anyone can help to fix bugs, or develop new features;) 
>>> For the short term, I think adding the man pages, documentation and some
>>> automation test programs/scripts would be very good. For the long term,
>>> I also have something new in my mind, maybe I should add a TODO to
>>> document it later.
>>>
>>> Well, the primary thing for now is to fix current bugs to make it really
>>> working, and I myself will spend more time on it these two weeks;)
>> If you have any bugs that you recognized already,Please you give me that
>> information?
> OK. A known issue is about the ticket revoking which I'm working on.
> Others I think I should look through the novell bugzilla first, and then
> send you the links or the description if you don't have a novell
> bugzilla account. Sure you're welcome to report issue and send patch
> here;)

OK! I will be waiting for it.

Thanks.
Taihun

>> And If we find booth bugs as we will send the report and patch as possible.
> Many many thanks;)
>
> Thanks,
> Jiaju
>
>
>
>