You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@rocketmq.apache.org by GitBox <gi...@apache.org> on 2022/08/10 08:58:51 UTC
[GitHub] [rocketmq] jason199101 opened a new issue, #4807: what will happen is metadata is different between Name Servers in one name server cluster?
jason199101 opened a new issue, #4807:
URL: https://github.com/apache/rocketmq/issues/4807
Here is the situation.
there is a name server cluster including ns1 and ns2. broker cluster including b1, b2, b3.
if ns1 is diconnected with b3, and ns2 is disconnected with b2, which means metadata in ns1 only include b1, b2 and ns2 only have b1, b3.
now if producer connected to ns1, producer will only send msg to b1 and b2.
if consumer connected to ns2, then consumer will only consume msg from b1 and b3. which means all msgs send to b2 will not be consumed. is that correct?
if this is correct, what should we do to prevent it happen?
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: dev-unsubscribe@rocketmq.apache.org.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] lizhanhui commented on issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by GitBox <gi...@apache.org>.
lizhanhui commented on issue #4807:
URL: https://github.com/apache/rocketmq/issues/4807#issuecomment-1211520759
This will make the cluster in an inconsistent state. Publishing of messages would be not load-balanced and subscribers may temporarily ignore some messages on the node that is not present in its route table. Some other undefined behavior may also be possible. This is pretty bad because this breaks the design assumption that brokers connect and report to all name-server nodes.
To avoid this from happening, it's advisable to build a monitor tool to compare the routing table of each topic periodically. Once a name server node fails, add an alternative one and isolate it from the cluster.
It may also be viable to introduce the consensus algorithm to name server nodes to further improve resilience.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: dev-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] francisoliverlee commented on issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by GitBox <gi...@apache.org>.
francisoliverlee commented on issue #4807:
URL: https://github.com/apache/rocketmq/issues/4807#issuecomment-1212186969
as I know, metadata in namesrv include kv config and topic route info that producers and consumers use for send and consume messages rely on.
<img width="467" alt="image" src="https://user-images.githubusercontent.com/5908412/184176811-baa1fd9a-15d5-4d06-999d-3be3724faf03.png">
how producers use topic route info when sending message:
https://github.com/apache/rocketmq/blob/e5a71bb95f6b8c1dcb4e44d5948469629da3833b/client/src/main/java/org/apache/rocketmq/client/impl/producer/DefaultMQProducerImpl.java#L550
for consumers, you try to find it.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: dev-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] jason199101 commented on issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by GitBox <gi...@apache.org>.
jason199101 commented on issue #4807:
URL: https://github.com/apache/rocketmq/issues/4807#issuecomment-1216187720
> This will make the cluster in an inconsistent state. Publishing of messages would be not load-balanced and subscribers may temporarily ignore some messages on the node that is not present in its route table. Some other undefined behavior may also be possible. This is pretty bad because this breaks the design assumption that brokers connect and report to all name-server nodes.
>
> To avoid this from happening, it's advisable to build a monitor tool to compare the routing table of each topic periodically. Once a name server node fails, add an alternative one and isolate it from the cluster.
>
> It may also be viable to introduce the consensus algorithm to name server nodes to further improve resilience.
gotta, thanks for your explanation :)
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: dev-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] github-actions[bot] closed issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by "github-actions[bot] (via GitHub)" <gi...@apache.org>.
github-actions[bot] closed issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
URL: https://github.com/apache/rocketmq/issues/4807
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: commits-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] jason199101 commented on issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by GitBox <gi...@apache.org>.
jason199101 commented on issue #4807:
URL: https://github.com/apache/rocketmq/issues/4807#issuecomment-1216193877
>
> as I know, metadata in namesrv include kv config and topic route info that producers and consumers use for send and consume messages rely on. <img alt="image" width="467" src="https://user-images.githubusercontent.com/5908412/184176811-baa1fd9a-15d5-4d06-999d-3be3724faf03.png">
>
> how producers use topic route info when sending message:
>
> https://github.com/apache/rocketmq/blob/e5a71bb95f6b8c1dcb4e44d5948469629da3833b/client/src/main/java/org/apache/rocketmq/client/impl/producer/DefaultMQProducerImpl.java#L550
>
> for consumers, you try to find it.
that's right, both consumer and producer will get the router info from name servers. However, just as my question described, if consumer and producer getting router info from different name server instances (in one name server cluster). which means consumer and producer may have different router info.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: dev-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] github-actions[bot] commented on issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by "github-actions[bot] (via GitHub)" <gi...@apache.org>.
github-actions[bot] commented on issue #4807:
URL: https://github.com/apache/rocketmq/issues/4807#issuecomment-1681418896
This issue is stale because it has been open for 365 days with no activity. It will be closed in 3 days if no further activity occurs.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: commits-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
[GitHub] [rocketmq] github-actions[bot] commented on issue #4807: what will happen if metadata is different between Name Servers in one name server cluster?
Posted by "github-actions[bot] (via GitHub)" <gi...@apache.org>.
github-actions[bot] commented on issue #4807:
URL: https://github.com/apache/rocketmq/issues/4807#issuecomment-1685135869
This issue was closed because it has been inactive for 3 days since being marked as stale.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: commits-unsubscribe@rocketmq.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org