Hi, I'm considering using Ceph to create a cluster across several data centres, with the strict requirement that writes should go to both DCs. This seems possible by specifying rules in the CRUSH map, with an understood latency hit resulting from purely synchronous writes. The part I'm unsure about is how the RADOS GW fits into this picture. For high availability (and to improve best-case latency on reads), we'd want to run a gateway in each data centre. However, the first paragraph of the following post suggests this is not possible: http://article.gmane.org/gmane.comp.file-systems.ceph.devel/12238 Is there a hard restriction on how many radosgw instances can run across the cluster, or is the point of the above post more about a performance hit? It seems to me it should be possible to run more than one radosgw, particularly if each instance communicates with a local OSD which can proxy reads/writes to the primary (which may or may not be DC-local). Thanks for any clarifications, Ben -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
