You are right, I should have not use the term asynchronous.
But in case of replication failure, for example network failure it will not 
fail a transaction.
So if I gradually lose connections, first between primary and backup and then 
between primary and client I will lose all send message between those events.
In case of cluster I may lose connection between primary and client if primary 
node decides to turn itself off after quorum vote.

> 27 мая 2022 г., в 00:31, Justin Bertram <[email protected]> написал(а):
> 
>> I think this is due to the fact that HA replication is asynchronous and
> replica server may not catch up with primary.
> 
> To be clear, message replication between a primary and a backup is
> *synchronous*.
> 
> 
> Justin
> 
> On Thu, May 26, 2022 at 3:11 AM Iliya Grushevskiy <[email protected]>
> wrote:
> 
>> Hi, Aaron
>> 
>> We are currently testing similar deployment and have encountered several
>> issues:
>> 
>> - message lose on send on network failure between data centers
>>  I think this is due to the fact that HA replication is asynchronous and
>> replica server may not catch up with primary.
>> 
>> - message lose or duplicate (depending on error handling strategy) on
>> consumer on network failure between data centers
>>  I think this was caused by two factors: duplicate id cache is consistent
>> only in HA pair and message redistribution was on.
>>  Switching off redistribution (or as an option increasing delay) should
>> fix this issue.
>> 
>> - message duplicate on mirrored server
>>  This is addressed in pull request:
>> https://github.com/apache/activemq-artemis/pull/4066
>> 
>> Regards
>> Iliya Grushevskiy
>> 
>> 
>>> 26 мая 2022 г., в 07:46, Justin Bertram <[email protected]>
>> написал(а):
>>> 
>>> I'm not aware of such a production deployment and I would be surprised if
>>> there was one given that clustering was designed for local area networks
>>> with low latency which typically isn't what is found between data
>> centers.
>>> 
>>> I recommend you pursue your mirroring approach as that is what mirroring
>>> was designed for (i.e. cross data-center disaster-recovery use-cases).
>>> 
>>> 
>>> Justin
>>> 
>>> On Wed, May 25, 2022 at 10:36 PM Steigerwald, Aaron
>>> <[email protected]> wrote:
>>> 
>>>> Hello,
>>>> 
>>>> Is anyone aware of a production deployment of an Artemis "cross data
>>>> center" HA cluster? For example, a cluster spread across 3 data centers.
>>>> Each data center contains a master/slave pair.
>>>> 
>>>> I would like to know what kind of issues anyone has overcome with such a
>>>> configuration. I understand there are many configuration and operational
>>>> variables. Any info would be helpful.
>>>> 
>>>> Note that we are considering asynchronously mirroring each master/slave
>>>> pair's queues to a dedicated asynchronous target node. The asynchronous
>>>> target node would exist in a different data center and would not service
>>>> any other connections. A custom plugin would automatically scale down
>> the
>>>> messages into a live cluster node if the connections to the master/slave
>>>> mirror sources were disconnected for a period of time.
>>>> 
>>>> Thank you,
>>>> Aaron Steigerwald
>>>> 
>> 
>> 

Reply via email to