Hi,
As of vSphere Replication 5.8 there are some useful graphics that could help you in your case.
If you have only 1:1 pair of sites, e.g. one source and one target site, then:
- go to the source site's VC
- Navigate to VC's Monitor -> vSphere Replication -> Reports
In this page you will notice several graphics that display different metrics. The one you are interested in is titled "Transferred bytes".
If you want more detailed information look at this blob on how you can retrieve information through vCenter Server's Events: http://www.virtu-al.net/2013/06/14/reporting-on-rpo-violations-from-vsphere-replication/ with PowerCLI. The same way but using hbr.primary.DeltaCompletedEvent event (more info on vSphere Replication events can be found here: List of vSphere Replication Events) you can extract and manipulate the data for your needs.
Another way of monitor this is by using the new feature in vSphere Replication 6.0 for network isolation by setting the replication traffic to a specific NIC and then monitor its traffic. See more info on traffic isolation feature in vSphere Replication 6.0 at Isolating the Network Traffic of vSphere Replication
Regards,
--Martin
Martin Marinov
VMware Software Engineer
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