Method and apparatus for cascaded replication using a multi splitter

摘要

Conventional method of replication do not allow cascaded replication with journaling. However, in example embodiments of the present invention, a splitter in storage or in the data path may split a single volume to multiple DPA targets. The splitter will intercept data arriving to the volume and split the data to another DPA, thereby allowing cascaded replication. In certain embodiments, the DPA may notify the splitter about a point of consistency because the DPA does not distribute IOs with write order fidelity at all times and only some points are write order fidelity consistent. Thus, the DPA may notify the splitter about a consistent point and the splitter will send notifications about the consistent points to the second DPA, allowing the volumes to have consistent points.

主权项

1. A method for cascaded replication using a splitter, the method comprising:
intercepting an input/output (IO) by a first splitter at a first site; splitting the IO by the first splitter at the first site to both a first volume at the first site and a first data protection appliance (DPA) at the first site; forwarding the IO from the first DPA at the first site to a second DPA at a second site; receiving the IO at the second DPA at the second site; intercepting the IO by a second splitter at the second site; splitting the IO by the second splitter at the second site to both a second volume at the second site, represented as a plurality of volume instances, and the second DPA at the second site by splitting the IO to a first volume instance of the second volume in a first consistency group with the first volume, to a second volume instance of the second volume in a second consistency group with the third volume, and to the second DPA; forwarding the IO from the second DPA at the second site for cascaded replication to a third DPA at a third site; receiving the IO at the third DPA at the third site; and processing the IO to a third volume at the third site.