bonding supports "static link aggregation" ?

2008-05-14
2013-06-06
  • In the "Bonding Driver HOWTO" I could not find a passage if the Linux bonding driver
    supports "static link aggregation"?

    And if so, which MODE will set up static aggregation?

    Or does the bonding driver support "dynamic link aggregation" only (mode 802.3ad or 4)?

    Thanx in advance for comments.

     
    • Paul Zirnik
      Paul Zirnik
      2008-05-14

      IMHO the balance-rr and balance-xor are the "static modes". They both requires switch configuration but no protocol. But only a view switches support balance-rr most support balance-xor.

      regards,
            Tami

       
    • Jay Vosburgh
      Jay Vosburgh
      2008-05-14

      "Static link aggregation" is, I suspect, a secret code word that means "Etherchannel," used by somebody who doesn't want to reference the term "Etherchannel" directly (which, if memory serves, is a trademark of Cisco).

      The Etherchannel-compatible modes in bonding are balance-xor and balance-rr.  The switch will have to be configured for Etherchannel (or whatever the switch vendor calls it) on the appropriate ports.

      Tami writes:
      IMHO the balance-rr and balance-xor are the "static modes". They both requires switch configuration but no protocol. But only a view switches support balance-rr most support balance-xor.

      While it is true that few switches support a round-robin Etherchannel balance algorithm, that doesn't matter when configuring bonding.  For Etherchannel (or for 802.3ad, for that matter) each side (bonding and the switch) can have different balance algorithms.  It's perfectly legal to set up bonding in balance-rr mode connected to a switch that does a MAC level XOR.

      Still, the balance-rr mode is rarely a good choice.  In most cases, the balance-xor (ideally with the layer3+4 or layer2+3 xmit_hash_policy) provides a better overall throughput.  The main reason for this is the packet reordering that typically occurs when using balance-rr; that causes various havoc with TCP/IP and other things.

       
    • Thanks for your epertise !

      Because I am not familiar in that detail I will have to
      do some more reading to understand the consequences for my project ...