Thanks for the quick reply.
At the moment it's not anywhere! We've brought the iSCSI SAN's but I've yet to deploy it - just designing it at the moment. Thinking of giving it it's own little vLAN with high QoS on it across the backbone.So it would be on it's own subnet with nothing else in the way.
I suppose I don't actually NEED it to be routable... more of something that I thought would be useful as the storage network will need to be routeable from the management network anyway, seems odd there's no option to allow it.
Just to be 100% sure, what I appear to have done is correct, and that ESXI doesn't allow an iSCSI VMK to have a default gateway on it?
Thanks again.