Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top


I have a storage server that has several virtual machine images stored on them. I would store them locally, but I have limited space on my desktop (using SSD storage). I would like to increase the bandwidth between the desktop and the storage server by using two NICs on each computer. My original configuration allowed about 55MBps between the desktop and storage server. This storage server also has several TBs of documents, pictures, movies, vms, and ISO/programs. The storage server has 8 1.5TB hard drives in a RAID 10 configuration with a hardware RAID controller. The benchmarks on the RAID 10 are about 300MBps.


In short, I am trying to bridge my switch and router. The switch is a small 8 port Cisco smart switch that supports 802.3ad LACP.

I have two computers plugged into the switch, each with 2 Intel Gigabit NICs.

The first computer is a Windows 7 machine that has the Intel ANS software installed. I have LACP configured with the computer and now show 3 NICs (2 Physical + 1 TEAM Virtual @ 2Gbps). It looks like this computer is configured correctly. I trunked the two ports that this computer is plugged into with the switch's web interface.

The second computer is a homebrew storage box running debian. I also have the bonding enabled on this machine and the switch configured with LACP.

Without having the WNDR3700 router in the picture yet, I am able to communicate between the Windows 7 machine and the debian box since they both have static IP addresses.

With LACP enabled on both machines I am getting about 106-108MBps speeds.


I plug in a network cable from the switch into the router and enable DHCP on the desktop. I saw no need to have a static address on the desktop. My transfer rates are still from 106MBps-108MBps. While this is still a boost, I am trying to figure out how to get about 140-180MBps. I am thinking that I need to increase the bandwidth from the router to the switch. My switch allows 4 groups for port trunking. I plugged in a second network cable from the router to the switch.

My question is, what is the proper way to fix this issue. Should I port trunk the two ports that are going from the switch to the router? Keep in mind that the router is a WNDR3700 and is unsure whether or not it supports LACP. I do have OpenWRT installed on the router, but it still wasn't clear in any documentation that I found if it supported 802.3ad LACP standards.

I am also wondering if there needs to be anything changed within the Cisco settings.

[Edit] - Corrected some numbers, wasn't really paying attention. It looks like the speeds though at least two NICs are bonded with LACP is still reaching the max bandwidth of one port. Is there a way to configure the switch so that I can increase this bandwidth? Also, on the storage server, I had a couple of extra NICs laying around and threw them on there as well.

enter image description here

enter image description here

enter image description here

enter image description here

Another EDIT and More Findings

I happened to look at the traffic of each individual NIC and think that I see the problem. I tested with a simple transfer for a 4GB file. I noticed that only one of the NICs was taking the load of the traffic. I then copied the file back to the Storage Server and noticed that the other NIC was sending out the traffic. I have 802.3ad LACP enabled on the two NICs and I see that it gets enabled dynamically on the switch's interface. Should I be using Static Link Aggregation?

enter image description here

enter image description here

share|improve this question
LACP bond two nic and load balance with the ip or mac... so from 1 to 1 your max bandwith stil 1gbps. – user179167 Dec 10 '12 at 3:25

You must log in to answer this question.

Browse other questions tagged .