I have 4 CentOS 7 boxes with SuperMico 10000BaseT NICs plugged into a Netgear ProSafe XS712T switch with Cat8 cables. Switch is all default settings, but shows NICs at 10G Full. NICs are configured:
(root@VH11 ~)# ethtool ens1f0 Settings for ens1f0: Supported ports: ( TP ) Supported link modes: 100baseT/Full 1000baseT/Full 10000baseT/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 10000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Speed: 10000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 0 Transceiver: internal Auto-negotiation: on MDI-X: Unknown Supports Wake-on: d Wake-on: d Current message level: 0x00000007 (7) drv probe link Link detected: yes
There are ONLY 10G NICs plugged into the switch.
I can only get transfer speeds of less than 1G on file transfers as reported by rsync, scp and iftop when transfering 1 20G file. When I test from server > switch > server with iperf, it tells me it gets 9.38 Gbits/sec, but I only get 10% of that on file transfers with rsync or scp.
What am I doing wrong here?
Thanks in advance for your time.