Lagg issue, cannot use full link of speed

[jackyho]

I have configured the network using Lagg. The network card is Gigabit link speed.
The network lagg0 speed alway stops at 1Gbps.

Please give me an advice :)

my cisco switch config:

#show running-config
interface Port-channel4
description FreeNas_LAGG_Group
switchport access vlan 18
switchport mode access
!

interface GigabitEthernet1/0/1
description FreeNas_LAGG
switchport access vlan 18
switchport mode access
spanning-tree portfast edge
channel-protocol lacp
channel-group 4 mode active
!
interface GigabitEthernet1/0/2
description FreeNas_LAGG
switchport access vlan 18
switchport mode access
spanning-tree portfast edge
channel-protocol lacp
channel-group 4 mode active
!

#show etherchannel summary
4 Po4(SU) LACP Gi1/0/1(P) Gi1/0/2(P)

#show interfaces port-channel 4
Port-channel4 is up, line protocol is up (connected)
Hardware is EtherChannel, address is
Description: FreeNas_LAGG_Group
MTU 1500 bytes, BW 2000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s, link type is auto, media type is unknown
input flow-control is off, output flow-control is unsupported
Members in this channel: Gi1/0/1 Gi1/0/2

 

[Fredda]

You seem to have a misunderstanding what link aggregation can achieve. You won't get a faster connection than 1 GB/sec for a client.
But you can get 2 clients operate at 1 GB/s each.

Also check the type of load-balancing which is configured for the port-channel. Setting the wrong mode there can basically make LACP useless,
when it is used to connect just one server.

 

[jackyho]

You seem to have a misunderstanding what link aggregation can achieve. You won't get a faster connection than 1 GB/sec for a client.
But you can get 2 clients operate at 1 GB/s each.

Also check the type of load-balancing which is configured for the port-channel. Setting the wrong mode there can basically make LACP useless,
when it is used to connect just one server.

thank you for replying me.

#1
If only one client access to FreeNAS server, they can transfer file ~116MB/s

#2
If 2 or 4 client access to the FreeNAS server at the same time, each client can only get 1/4 of 116MB/s

I checked the network status of FreeNAS, the total transfer speed of lagg0 is only 116MB/s. I thought it must be ~232MB/s.

type of load-balancing on switch is src-dst-ip

 

[Fredda]

Keep in mind that with just 2 clients and a LAGG consisting of 2 port you have a 50% chance both connections go through the same channel
and so resulting in a 1GB/s speed. But with 4 clients this chance is very little.

You should check with iperf if the network is really the limiting factor. Start the iperf Server on you FreeNAS box (iperf -s)
and run simultaneously the iperf client on your clients (iperf -c <ip-of-FreeNASBox>) and see if you still get 1GB/s total bandwidth.