[Bucardo-general] Bucardo question

Женя Деревянкин jekader at gmail.com
Tue Dec 8 23:41:05 UTC 2009


That would be the perfect way! I just thought it's impossible for some reason.
In this case I can even set a bucardo instance on every server, that
will just sync two servers.
So when one server and bucardo instance dies, nothing happens!

Or even better - each server hosts a bucardo instance, which pushes
the changes to two(or even more)
other servers, but doesn't pull changes. This way, when something's
written into a database, bucardo
sends the change to the other servers automatically.

Is that possible?

2009/12/9 Itamar Reis Peixoto <itamar at ispbrasil.com.br>:
> On Tue, Dec 8, 2009 at 8:51 PM, Женя Деревянкин <jekader at gmail.com> wrote:
>> Hi, Greg.
>>
>> Thanks for the info.
>>
>> My question is in making any of the two remaining servers syncronised.
>> So, if I have three servers, A, B and C, they'e sync'ed the following way:
>> A => B
>> A => C
>>
>> All of them have read-write access, and produce database changes.
>>
>> So, if A goes down, I must start sync'ing B => С.
>> When A goes back online, the db contents are manually cleared,
>> pulled from B, and A becomes a "slave", so we have:
>> B => С
>> B => A
>>
>> Until B fails, and the system returns to the initial state.
>>
>> Of cource, that's the worst-case scenario. The chances that specifically the
>> "master" database fails are pretty low, but I can't exclude such a possibility.
>>
>> So I wanted to know if it's safe to switch "masters" in a way I've described.
>> As I've understood, the delta tables just accumulate changes since last sync,
>> so it should work, but I could be missing something.
>>
>> --
>> Best regards,
>> Eugen
>>
>> 2009/12/8 Greg Sabino Mullane <greg at endpoint.com>:
>>>> So, my goal is to make several "clone" databases (3 or more), which
>>>> must be kept in sync even after one of them fails. After recovery the
>>>> database can be put in operation manually.
>>>>
>>>> But if the server that fails is the one bucardo is running on? What
>>>> must happen then? I mean not just that postgres dies, but the whole
>>>> server. A new instance of bucaurdo should start running on one of the
>>>> remaining servers, keeping the data synced? Won't that interfere into
>>>> the database structure?
>>>
>>> You can put Bucardo anywhere, and have backup copies on other servers
>>> ready to go. While you could even use Bucardo to replicate the bucardo
>>> database :), it's small enough that a pg_dump will suffice.
>>>
>>> It's unclear what your scenario is as far as failing slaves, but Bucardo
>>> should be able to handle that. In the future it will be automatic, but
>>> generally, if a slave goes down, you set that database as "inactive"
>>> inside Bucardo and restart it. When it comes back up, just set the db to
>>> "active" and restart Bucardo again.
>>>
>>> --
>>> Greg Sabino Mullane greg at endpoint.com
>>> End Point Corporation
>>> PGP Key: 0x14964AC8
>> _______________________________________________
>
>
> why not this -->
>
> A -> B
> B -> A
>
> A-> C
>
>
>
>
>
> --
> ------------
>
> Itamar Reis Peixoto
>
> e-mail/msn/google talk/sip: itamar at ispbrasil.com.br
> skype: itamarjp
> icq: 81053601
> +55 11 4063 5033
> +55 34 3221 8599
>



-- 
С уважением,
Женя Деревянкин


More information about the Bucardo-general mailing list