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https://issues.apache.org/jira/browse/COUCHDB-782?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12875204#action_12875204
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Randall Leeds commented on COUCHDB-782:
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Damien, I originally reasoned that this was a good thing because the identity
of a database would follow the database itself. I now realize that while this
is great for moving dbs it's a disaster for copying them because you create two
(possibly diverging) instances which claim to be the same.
Regarding a canonical format, how does this simple idea sound:
Generate a random uuid on the #db record, but do not write it out in the
header. This way, dbs have a new uuid every time they're opened. Then, the
replicator can try to open the bare db name at the end of the URI locally and
compare that to the uuid returned from the http info. Then, local dbs can be
detected and canonicalized to the bare db name without relying on hostname
information that is sensitive to system/dns configuration problems.
As a side bonus, replicating a database to itself could *always* be detected at
the outset, which reduces the checkpoint conflict scenarios to only ones in
which a previous checkpoint save succeeded but the client timed out waiting for
the reply, at which point replication should safely restart gracefully. I'm
happy to put this together later.
> Restarting replication
> -----------------------
>
> Key: COUCHDB-782
> URL: https://issues.apache.org/jira/browse/COUCHDB-782
> Project: CouchDB
> Issue Type: Bug
> Components: Replication
> Affects Versions: 0.10
> Environment: Ubuntu, 9.10
> Reporter: Till Klampaeckel
>
> So we had to restart replication on a server and here's something I noticed.
> At first I restarted the replication via the following command from localhost:
> curl -X POST -d '{"source":"http://localhost:5984/foo";,
> "target":"http://remote:5984/foo"}' http://localhost:5984/_replicate
> In response, futon stats:
> W Processed source update #176841152
> That part is great.
> Last night I did not have immediate access to the shell so I restarted
> replication from remote (through curl on my mobile):
> curl -X POST -d '{"source":"http://user:[email protected]:5984/foo";,
> "target":"http://remote:5984/foo"}'
> http://user:[email protected]:5984/_replicate
> The response in futon this morning:
> W Processed source update #1066
> ... and it kept sitting there like it was stalled and only continued in
> smaller increments.
> I restarted CouchDB and restarted from localhost - instant jump to 176
> million.
> I'm just wondering what might be different accept for that one is against the
> public interface, vs. localhost. I'd assume that replication behaves the same
> regardless.
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