Hello, all?
I'm new to this website.
My name is Jeongsook Park.
Today, I'm here to ask a question about network bonding with alb mode.
(adaptive load balancing)

I tried to test NIC bonding with two servers.
They are on CentOS 6.3 and have 2 NIC cards(igb)of each.
But the result was a little bit disappointing.

I think that system configuration is consistent with Linux Ethernet Bonding Driver HOWTO document:

- /etc/sysconfig/network-scripts/ifcfg-bond0 --> master
- /etc/sysconfig/network-scripts/ifcfg-eth2 --> slave
- /etc/sysconfig/network-scripts/ifcfg-eth3 --> slave
- /etc/modprobe.d/bonding.conf --> mode=6 miimon=100.

I checked bonding status with this command:

- cat /proc/net/bonding/bond0

I tested bonding performance with iperf tool to check if bonding was working correctly.

- server 1: iperf -s -p 5002, iperf -s -p 5003
- server 2: iperf -c 192.168.0.xx -t 20 -p 5002,
iperf -c 192.168.0.xx -t 20 -p 5003

I had expected that network performance would reach roughly 2Gbps altogether.
But, the result showed that performance was only 500Mbps for each client.

Is this result correct or wrong?
If it is wrong, what should I do for NIC bonding?
Anyone who knows, please answer for my question.

Thank you.

Best regards,
Jeongsook.

Window size also affect network performance, what is your window size?

Dear Vishesh,

I tested again with changed window sizes defined in /proc/sys/net/ipv4/tcp_wmem and /proc/sys/net/ipv4/tcp_rmem.
. /proc/sys/net/ipv4/tcp_wmem : 4096 16384 4194304 --> 4096 87380 4194304
. /proc/sys/net/ipv4/tcp_rmem : 4096 87380 4194304

Better performance, but still less than 1G.(940Mbps --> 960Mbps) :-(

Thank you, Vishesh.


Best regards,
Jeongsook.