I have a strange issue with NFS provisioned datastore in VMware environment.
For some twisted reason I can achieve only somewhere around 5.6Gbit/s which is far from 10Gbit/s network speed between the storage and the ESXi.
We have 4 x 10Gbit/s ports used for NFS data. They are configured according to the best practices to the upstream switches.
NetApp: NetApp Release 9.6P3
ESXi: VMware ESXi, 6.7.0, 15160138
The described throughput was observed first with storage vmotion which appeared somehow limited.
We have carefully examined our configuration, and now the best practices described on the link below are also in place.
https://library.netapp.com/ecmdocs/ECMLP2843689/html/GUID-346ACB95-6AD4-4DEA-8901-C9697AC3530F.html
However "the limit" is still there.
In addition, I have verified the speed with network test-link run-test -vserver my-veserver -destination ip.addr.of.iperf
ran from Netapp toward VM running an iperf on the ESXi host itself.
I found a discussion related to the similar issue, but unfortunately did not helped me. Somehow the network behave as half duplex.
Any suggestions or help will be greatly appreciated.