[
https://issues.apache.org/jira/browse/CASSANDRA-10134?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15256555#comment-15256555
]
Sam Tunnicliffe commented on CASSANDRA-10134:
---------------------------------------------
Regarding {{DynamicEndpointSnitch}}, I came to the same conclusion as you, that
the coupling was there to control the init order more than anything else and
that in all likelihood was no longer necessary. I was keen to avoid scope creep
by this point, so erred on the side of caution in preserving existing
behaviour. I'm pretty sure it could just be removed though, so I'll open a
separate ticket for that.
> Always require replace_address to replace existing address
> ----------------------------------------------------------
>
> Key: CASSANDRA-10134
> URL: https://issues.apache.org/jira/browse/CASSANDRA-10134
> Project: Cassandra
> Issue Type: Improvement
> Components: Distributed Metadata
> Reporter: Tyler Hobbs
> Assignee: Sam Tunnicliffe
> Labels: docs-impacting
> Fix For: 3.x
>
>
> Normally, when a node is started from a clean state with the same address as
> an existing down node, it will fail to start with an error like this:
> {noformat}
> ERROR [main] 2015-08-19 15:07:51,577 CassandraDaemon.java:554 - Exception
> encountered during startup
> java.lang.RuntimeException: A node with address /127.0.0.3 already exists,
> cancelling join. Use cassandra.replace_address if you want to replace this
> node.
> at
> org.apache.cassandra.service.StorageService.checkForEndpointCollision(StorageService.java:543)
> ~[main/:na]
> at
> org.apache.cassandra.service.StorageService.prepareToJoin(StorageService.java:783)
> ~[main/:na]
> at
> org.apache.cassandra.service.StorageService.initServer(StorageService.java:720)
> ~[main/:na]
> at
> org.apache.cassandra.service.StorageService.initServer(StorageService.java:611)
> ~[main/:na]
> at
> org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:378)
> [main/:na]
> at
> org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:537)
> [main/:na]
> at
> org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:626)
> [main/:na]
> {noformat}
> However, if {{auto_bootstrap}} is set to false or the node is in its own seed
> list, it will not throw this error and will start normally. The new node
> then takes over the host ID of the old node (even if the tokens are
> different), and the only message you will see is a warning in the other
> nodes' logs:
> {noformat}
> logger.warn("Changing {}'s host ID from {} to {}", endpoint, storedId,
> hostId);
> {noformat}
> This could cause an operator to accidentally wipe out the token information
> for a down node without replacing it. To fix this, we should check for an
> endpoint collision even if {{auto_bootstrap}} is false or the node is a seed.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
