Celerra replication

Hi,

We are upgrading our main Datacenter and are replacing our central Celerra with an Isilon. Our periphery offices will still be using Celerra's going forward. For DR and Backup we replicate all CIFS data from these periphery offices to the main Datacenter, this is via the native Celerra replicator, this will have to change because of the upgrade.

I'm looking for solutions of a way to replicate the CIFS data into the main Datacenter, hopefully in a continuous drip feed method, asynchronous, similar to the replicator. Even if solutions have been quite inventive i.e. do EMC produce a virtual celerra that I can put on VMware at the Datacenter site, or a virtual ONE FS I can put at the source site to replicate? If not and third party replication tools have been purchased, which one's? and how did it work with knowing how the file system files changes, if its done via a separate box.

Regards

Andrew