According to VMware KB using JumboFrames inside VM is not supported in vSphere 5 with vmxnet3 network adapter. Therefore StarWind Software doesn`t support following scenarios untill VMware will not provide an updated version of VMTools:
1) Connecting with iSCSI initiator running inside VM hosted on vSphere 5 directly to StarWind iSCSI targets with JumboFrames enabled inside this VM and vmxnet3 adapter used with VMTools 5 installed. Please note: due to possible performance degradation associated with disabled Jumbo Frames the abovementioned configuration is not recommended.
Meanwhile StarWind Software fully supports and recommends following scenarios with JumboFrames enabled:
1) Using StarWind iSCSI targets as VMFS datastore
2) Using StarWind iSCSI targets as RDM (Raw Device Mapping) for VM in physical and virtual compatibility mode.
3) Using VMTools and vmxnet3 driver from vSphere 4 (can be downloaded here)
4) Connecting with iSCSI initiator running inside VM hosted on vSphere 5 directly to StarWind iSCSI targets with JumboFrames enabled inside this VM and vmxnet2 (Enhanced) or E1000 adapter used with VMTools 5 installed.
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