I'm quite new to ESXi but I seem to be having an issue I can't manage to google up a solution for.
I have a Dell T420 running ESXi 6.7 with several guests on (Windows/Linux/other). When I try to transfer a file via CLI or GUI from a local data store to either a remote NFS share or just download/upload via the browser the performance is poor, around 115Mbps (yes, bits) upload to a remote share/PC. Doing the same test from one of the guests shows no issues and I get 800Mbps+
Are there any limitations around what the ESXi management port can do, maybe to stop it impacting guests? All ports(management and guests) are on a vSwitch with a 2 x 1Gb connection to the physical switch.
Traffic going through the management vmkernel is not optimized for those types of transfers and can also be limited by SSL. The management vmkernel interface is designed for exactly that--management, not bulk file transfers. Copying through the guest does not use the management interface.