Network speed slow from host to LAN (200 Mb/s)

[sdrwtf]

Hello,

I have looked at several posts here in the forum on this topic, but I can't get any further.

The network connection from my PVE host to the LAN is only about 100 to maximum 200 MBytes/sec. I have tested this with iperf3 (logs below), ethtool shows that the NIC is correctly recognized with 1000Mb/s Full Duplex:

Settings for enp0s25:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 2
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: off (auto)
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000007 (7)
                               drv probe link
        Link detected: yes

iperf3 client log:

[  5] local 192.168.100.10 port 40912 connected to 192.168.101.54 port 5201
[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec   113 MBytes   113 MBytes/sec    0    419 KBytes       
[  5]   1.00-2.00   sec   111 MBytes   111 MBytes/sec    0    482 KBytes       
[  5]   2.00-3.00   sec   112 MBytes   112 MBytes/sec    0    530 KBytes       
[  5]   3.00-4.00   sec   111 MBytes   111 MBytes/sec    0    530 KBytes       
[  5]   4.00-5.00   sec   112 MBytes   112 MBytes/sec    0    530 KBytes       
[  5]   5.00-6.00   sec   112 MBytes   112 MBytes/sec    0    559 KBytes       
[  5]   6.00-7.00   sec   112 MBytes   112 MBytes/sec    0    559 KBytes       
[  5]   7.00-8.00   sec   112 MBytes   112 MBytes/sec    0    650 KBytes       
[  5]   8.00-9.00   sec   111 MBytes   111 MBytes/sec    0    691 KBytes       
[  5]   9.00-10.00  sec   112 MBytes   112 MBytes/sec    0    691 KBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec  1.09 GBytes   112 MBytes/sec    0             sender
[  5]   0.00-10.00  sec  1.09 GBytes   111 MBytes/sec                  receiver

System info:

• Proxmox VE 6.2-6 (all updates installed)
• Mainboard: Intel S5500BC (with latest firmware)
• NIC onboard: Intel 82567LM-2 / 82574L
• NIC PCIe: Intel X550T
• CPU: 2 x Intel E5649
• RAM: 32 GB ECC DDR3 @ 1333 MT/s
• HDD setup (on Intel RS2BL080):
  • Host: RAID1 with 2 x 1 TB Samsung Evo SSD
  • VM Storage: RAID10 with 4 x 4 TB WD Red

The switch is not the problem I think, when I test from my laptop to another PC (both plugged directly into the switch) I get about 950 MBytes/s via iperf3, the cabling is continuous with CAT6 cables. I also installed a PCIe 10GB/s card (Intel X550T) for testing with the same result.

Does anyone have any idea what could be causing it?

Thanks a lot!

Best regards
Patrick

 

[spirit]

local 192.168.100.10 port 40912 connected to 192.168.101.54 port 5201

is it 2 differents /24 network ?

if yes, are you sure that the limitation is not on the gateway/router ?

 

[sdrwtf]

is it 2 differents /24 network ?

if yes, are you sure that the limitation is not on the gateway/router ?

Thanks for the reply!

It is one 192.168.100.0/22 network, 192.168.100.1 - 192.168.101.254 with a subnet mask of 255.255.252.0. Have it like that to have 254 adresses for static IPs, DHCP starting at 192.168.101.1.

To be sure i tested again withtwo clients manually set up to 192.168.100.200 and 192.168.101.54 - and same issue. Therefore I think it's related to the switch or firewall (Unifi devices), I'll check this up in the Unifi forum and post an update for other people which may encounter similar issues.

 

[fabian]

1Gbit/s is 125,000,000 B/s is ~120MB/s, sprinkle in a little bit of overhead and your results are looking quite good I'd say.