[
https://issues.apache.org/jira/browse/CASSANDRA-10134?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15210289#comment-15210289
]
Paulo Motta commented on CASSANDRA-10134:
-----------------------------------------
Since we are talking about gossip startup checks with {{auto_bootstrap=false}},
it would probably be a good idea to also validate for token collisions with
other nodes during startup. A possible scenario is to replace a node with
another node, and then start the original node which will override the replaced
node in the ring and generate chaos (just tested on ccm and this is an allowed
scenario). Other cases are operator errors when setting the tokens manually.
> 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
> 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)
