Channel-bonding 2.2 vs 2.4?

Mike Weller weller at
Mon Aug 6 14:27:55 PDT 2001

Hello, I started a thread on the list about a month ago, and I've
finally found some time to play with channel-bonding again.  I'm
still  having problems.

Here's a memory-refresher:

My switch (HP Procurve 4000) supports load-balancing/trunking and
VLANs.  I was taking the wrong approach, apparently.

1) At first, I was attempted to do load-balancing with the switch. I'd
   create individual trunk groups for the channel-bonded ports.  This
   had moderate success, but wasn't what I wanted since the switch
   would distribute traffic based on the source address.  I could
   never get 200Mbps this way.

2) Someone on the beowulf at mailing list suggested setting
   up a VLAN.  I created 2 VLANs to isolate the networks.  To make a
   long story short, my switch supports VLANs, but duplicate MAC
   addresses confuse it.

3) I followed up on this suggestion provided by Jakob:

  From: <jakob at> 
  >You can buy separate switches, unmanaged dirt cheap ones.  
  >Trunking N nics per node, requires N switches.
  >This works, is simple, and it's cheap.

   I tried dirt cheap linksys switches... put all eth0's on 1 switch
   and all eth1's on the other switch.  The RX and TX's are even on
   both sides.  I can communicate with it.  Unfortunately, I only
   achieve 50Mbps as opposed to 200Mbps :-( Using the same hardware
   and OS, I achieve 100Mbps in un-channel-bonded mode.

4) Someone else on the list wrote:

From: R C <zarquon at>
  >As you found out, the HPs don't support duplicate NATs on seperate 
  >VLANs (even states this in the manual, but I had to dig to find it).
  >At that point I borrowed the lab switch and hooked it in.  Using
  >2.4.x, and 2 channels, I got about 160-170 Mbps with an Intel eepro100
  >(onboard) and an Adaptec duralan (starfire?) card.  The adaptec
  >tended to hiccup and give "Something Wicked Happened!" during full
  >speed tests, but rarely pulled down below 150 Mbps.
  >Tests were done using ttcp, linux 2.4.4?, and Dell server boxes
  >(dual 500, 512MB).

   I noticed that he was using the 2.4 kernel and Scyld was still
   using 2.2.  I started to wonder if there were bonding issues with
   the 2.2 kernel.  I decided to take Scyld out of the equation and
   using 2 linux boxes with the 2.4.7 kernel (with a mandrake base):

[root at n0 /tmp]# uname -a
Linux n0 2.4.7mw2 #2 Tue Jul 24 19:54:20 CDT 2001 i686 unknown

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