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https://issues.apache.org/jira/browse/COUCHDB-1259?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13490424#comment-13490424
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Benoit Chesneau commented on COUCHDB-1259:
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I don't. The replication is fundamentally a peer to peer protocol. or master to
master. whatever.
It is and should be expected that a node can disappear for many reasons.
Relying on a server id is one of the possibilities to restart automatically a
replication, other would use other parameters based on the ip and the location,
etc... It is the responsibility of the application to know that. As a protocol
the replication shouldn't force this way imo. As a client the replicator
shouldn't too. It is already doing the best effort imo: ie restarting for the
same ip, port and properties of the replication.
As a side note, this is one of the reason the 0 port could be used here instead
of letting your *application* fix a port. 0 won't change. And you could rely
with the *application* on a unique property in the replication properties.
> Replication ID is not stable if local server has a dynamic port number
> ----------------------------------------------------------------------
>
> Key: COUCHDB-1259
> URL: https://issues.apache.org/jira/browse/COUCHDB-1259
> Project: CouchDB
> Issue Type: Bug
> Components: Replication
> Affects Versions: 1.1
> Reporter: Jens Alfke
> Assignee: Robert Newson
> Priority: Blocker
> Fix For: 1.3
>
> Attachments: couchdb-1259.patch, couchdb-1259.patch
>
>
> I noticed that when Couchbase Mobile running on iOS replicates to/from a
> remote server (on iriscouch in this case), the replication has to fetch the
> full _changes feed every time it starts. Filipe helped me track down the
> problem -- the replication ID is coming out different every time. The reason
> for this is that the local port number, which is one of the inputs to the
> hash that generates the replication ID, is randomly assigned by the OS. (I.e.
> it uses a port number of 0 when opening its listener socket.) This is because
> there could be multiple apps using Couchbase Mobile running on the same
> device and we can't have their ports colliding.
> The underlying problem is that CouchDB is attempting to generate a unique ID
> for a particular pair of {source, destination} databases, but it's basing it
> on attributes that aren't fundamental to the database and can change, like
> the hostname or port number.
> One solution, proposed by Filipe and me, is to assign each database (or each
> server?) a random UUID when it's created, and use that to generate
> replication IDs.
> Another solution, proposed by Damien, is to have CouchDB let the client work
> out the replication ID on its own, and set it as a property in the
> replication document (or the JSON body of a _replicate request.) This is even
> more flexible and will handle tricky scenarios like full P2P replication
> where there may be no low-level way to uniquely identify the remote database
> being synced with.
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