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I'd suggest monitoring overall replications status with a combination of log monitoring and swift-dispersion-report. If you find something that is under-replicated, you can run the replicator process and give it a list of partitions to prioritize. http://docs.openstack.org/developer/swift/admin_guide.html#dispersion-report I'd recommend running dispersion report with 100% coverage.

However, your question implies that when an object is created it is not durable in the system. That's not the case. Swift will not return with a success unless the data has been durably persisted in the cluster (a quorum of writes). Quorum is determined per storage policy; in a replicated policy, quorum is half + 1 for odd numbers of replicas and half for even numbers of replicas. This means that when a client gets a 201 response to an object PUT request, that object has been stored at least 2 times in a 3-replica storage policy (and it's extraordinarily likely it was stored a full 3 times).

Let me know if you want more details about this.

--John




On 4 Dec 2016, at 14:56, Mark Kirkwood wrote:

> Suppose you have a newly created object, and want to ensure it has replicated (i.e this object is 'special' in some way). If the replication process is taking a while, is it sensible to 'encourage' Swift replication via direct HTTP calls using the 'replicate' method (or is this dangerous)?
>
>
> E.g:
>
> markir at obj4:/srv/node/vdb/objects/5$ ls 55e
> ls: cannot access '55e': No such file or directory
>
> markir at obj1:~$ curl -v -X REPLICATE "http://obj4:6000/vdb/5/55e"
>
> markir at obj4:/srv/node/vdb/objects/5$ sleep 30;ls 55e
> 5c38bfdd63f01a8e56260105fc68555e
>
>
> regards
>
>
> Mark
>
>
>
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