I have sent a PR for the mirror issues: https://github.com/apache/activemq-artemis/pull/4127
On Wed, Jun 1, 2022 at 10:06 AM Stephen Baker <stephen.ba...@rmssoftwareinc.com> wrote: > > I’m not on the DBA team so I don’t know specifics but it is asynchronous > replication to a secondary server in the same datacenter and a similar > primary/secondary server to the standby datacenter. > > Theoretically the mirroring in Artemis should offer the same resiliency > (synced to the disk, possibly not replicated in the event of a hard failure); > But in practice mirroring is Artemis is relatively new and SQL replication > has existed for decades with plenty of DBAs who are well versed in mitigating > common problems. > > Some of the issues we have with mirroring that I can remember: > * The two sides get out of sync quickly as in: > https://issues.apache.org/jira/projects/ARTEMIS/issues/ARTEMIS-3766 > (not just the expiry queue – looking at one of our production sets right > now on > two of 6 queues I see message counts of 172 and 96 on the cold side, and 0 > on the hot side. Because this is Artemis 2.20 I cannot browse them or see > if they > are really there but I hope to learn more when we complete our 2.22 > update.) > * The stats are not tracked correctly so it’s hard to tell how out of sync > we are: https://issues.apache.org/jira/projects/ARTEMIS/issues/ARTEMIS-3743 > * We use to end up with extremely large journals on the cold side that would > prevent start up. Mitigated with aggressive TTL and purging on the cold > side. > * We’ve ended up with delivery of ancient messages when failing over. > Mitigated > somewhat with aggressive TTL. > * More often than not when performing a graceful failover we need to restart > Artemis > on the new live. Consumers connect but they don’t receive any messages. > * In some instances the mirror queues have not shown up in the Artemis console > but have functioned. No known steps to reproduce, in all cases eventually > resolved > themselves. > > * Messages in the logs that indicate problems we don’t know the effect of > like: > > 2022-05-30 00:30:12,964 WARN > [org.apache.activemq.artemis.protocol.amqp.connect.mirror.AMQPMirrorControllerTarget] > Queue activemq.management.665d289a-520e-40a6-9233-96265817ca6c not found on > mirror target, ignoring ack for > queue=activemq.management.665d289a-520e-40a6-9233-96265817ca6c, > messageID=68514641673, nodeID=dea32b83-efd5-11eb-b5b1-0050568fe3b2 > > > I hope as we grow we’ll be able to devote a resource to working on Artemis. > It’s a critical and highly performant part of our infrastructure. I have > personally been > advocating for it to replace our aging JbossMQ 4 (pre-hornet) infrastructure. > > The JDBC replication is part of that plan, to replace a similarly JDBC > replicated > JbossMQ 4 cluster that is for the first time, outside of products that I’m > directly > responsible for. > > A bit more than I intended to write, but I hope this helps understand our > where > we are and our motivations. > > > From: Justin Bertram <jbert...@apache.org> > Date: Wednesday, June 1, 2022 at 12:34 AM > To: users@activemq.apache.org <users@activemq.apache.org> > Subject: Re: Artemis MQ with JDBC persistence not starting since 2.22 update > I sent a commit to update the docs in the repo, and I also updated the > website. > > Out of curiosity, how is your MySQL replication configured? Are you using > the default asynchronous, semisynchronous, or fully synchronous NDB cluster? > > > Justin > > On Tue, May 31, 2022 at 4:09 PM Stephen Baker < > stephen.ba...@rmssoftwareinc.com> wrote: > > > Understood thank you. We (the company I work for) are definitely getting > > more value out of the product than we are contributing, so that point is > > taken. The JDBC replication route was recommended by a consultant from > > Savoir as more established/reliable than mirroring when delivery guarantees > > are important, which is why we are pursuing it. > > > > > [EXTERNAL]: This email originated from outside of Rave Mobile Safety. Do not > click links or open attachments unless you recognize the sender and know the > content is safe. -- Clebert Suconic
