1

May i have some question about interface configuration ? I want to use 4 ports gigabit bonding on centos6. Is linux limited speed below full ports( 4 * 1GB) by default or not? I cannot use speed more than 2 GB.

Thank you in advance.

The Cattery
  • 21
  • 3
  • In general, if you need to grow beyond 1Gb, you're best just moving to 10Gb interfaces. – EEAA Oct 30 '15 at 11:59

1 Answers1

2

It depends on the bonding mode in use and the nature of the traffic flowing across the connection.

Start by reviewing this: https://www.kernel.org/doc/Documentation/networking/bonding.txt Pay particular attention to section "12.1.1 MT Bonding Mode Selection for Single Switch Topology"

You might be able to achieve what you want with a "balance-rr" bond. I've never personally been very satisfied with these though - others might have better experiences.

Generally speaking a 4x1Gb bond is going to give you a 1Gb connection that's 4x harder to saturate rather than just a 4Gb connection. The reason being that in most bonding modes the kernel will select a particular interface within the bond to send all the traffic for either a particular connection or host thru. This is referred to as the transmit hash policy in the above document. With a sufficient diversity of hosts/connections the load becomes equally balanced across the individual links, but no one connection will exceed the maximum speed of an individual link (obviously).

Brandon Xavier
  • 2,022
  • 13
  • 15
  • Thank you for your suggestion i forgot to tell you with my config. I've used bond mode 4. – The Cattery Oct 31 '15 at 14:15
  • If you're expecting to get more than 1Gb/sec from a single connection (such as a simple file transfer), it won't happen with mode 4. OTOH, if you're hoping to get an aggregate thruput of 4Gb/sec from MANY connections, a properly configured mode 4 bond should do the trick. It comes down to your expectations and the nature of the traffic. – Brandon Xavier Nov 01 '15 at 11:05