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https://issues.apache.org/jira/browse/CASSANDRA-11559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16526011#comment-16526011
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Dinesh Joshi commented on CASSANDRA-11559:
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I like this idea on the whole. One comment is that a "Endpoint" may not have 
just one IP address. This is especially true during streaming where a peer can 
have two potentially different IP addresses. This is not adequately addressed 
by simply renaming {{InetAddressAndPort}} (See: {{StreamSession}} diff here - 
[https://github.com/apache/cassandra/compare/trunk...alourie:CASSANDRA-11559#diff-b397cc5438b1a4be20f026c9ec9ecd6e]).
 You want to address such use-cases to demonstrate the value of this refactor.

 

 

> Enhance node representation
> ---------------------------
>
>                 Key: CASSANDRA-11559
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-11559
>             Project: Cassandra
>          Issue Type: Sub-task
>          Components: Distributed Metadata
>            Reporter: Paulo Motta
>            Assignee: Alex Lourie
>            Priority: Minor
>
> We currently represent nodes as {{InetAddress}} objects on {{TokenMetadata}}, 
> what causes difficulties when replacing a node with the same address (see 
> CASSANDRA-8523 and CASSANDRA-9244).
> Since CASSANDRA-4120 we index hosts by {{UUID}} in gossip, so I think it's 
> time to move that representation to {{TokenMetadata}}.
> I propose representing nodes as {{InetAddress, UUID}} pairs on 
> {{TokenMetadata}}, encapsulated in a {{VirtualNode}} interface, so it will 
> backward compatible with the current representation, while still allowing us 
> to enhance it in the future with additional metadata (and improved vnode 
> handling) if needed.
> This change will probably affect interfaces of internal classes like 
> {{TokenMetadata}} and {{AbstractReplicationStrategy}}, so I'd like to hear 
> from integrators and other developers if it's possible to change these 
> without major hassle or if we need to wait until 4.0.
> Besides updating {{TokenMetadata}} and {{AbstractReplicationStrategy}} (and 
> subclasses),  we will also need to replace all {{InetAddress}} uses with 
> {{VirtualNode.getEndpoint()}} calls on {{StorageService}} and related classes 
> and tests. We would probably already be able to replace some 
> {{TokenMetadata.getHostId(InetAddress endpoint)}} calls with 
> {{VirtualNode.getHostId()}}.
> While we will still be dealing with {{InetAddress}} on {{StorageService}} in 
> this initial stage, in the future I think we should pass {{VirtualNode}} 
> instances around and only translate from {{VirtualNode}} to {{InetAddress}} 
> in the network layer.
> Public interfaces like {{IEndpointSnitch}} will not be affected by this.



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