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Jason Smith commented on COUCHDB-1259: -------------------------------------- Couch already has a unique identifier: its URL. I'm not sure another per-server UUID buys you much. With a second unique identifier, you can determine that (this couch has moved on the Internet || this couch has a configuration error). Maybe the first condition is more likely. Meh. Couch already has a per-server UUID: _config/couch_httpd_auth/secret. Hashing this value can produce a public unique ID. Normal users may not read the config, so you have to expose this value to them somehow. Is that a new global handler? Or is it added to the {"couchdb":"Welcome"} response? For these reasons, I'm not sure the solution is to assign a random UUID to the Couch. > 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 > > 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. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira