From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Date: Sun, 06 Apr 2003 12:21:08 +0000 Subject: Re: [LARTC] Multipath and equalize. Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lartc@vger.kernel.org N N Ashok wrote: > I understand the concept of multipath in routing but dont know how the >'equalize' option affects routing. From what I read, multipath specifies a >list of interfaces (nexthops) to use for a given route. Whenever a route is >looked up in the FIB, each interface (nexthop) is used according the 'weight' >assigned to it during the route setup. By default the weights are assigned a >value of 1 which results in each of the interface being used approximately >equally. > I read that 'equalize' option is suppossed to distribute the load on a >per-packet basis. But the stock kernel does not seem to do it. I read the >equalize patch provided by Patrick McHardy, at >http://trash.net/~kaber/. This does achieve the per-packet load-balancing. > I wanted to know what does the 'equalize' option do in the kernel without >this patch. Can anyone help me with this? > Without the patch the kernel does nothing. An exact desciption how it works is included in the patch. Please make sure you understand the problems of per-packet loadbalancing before using it. If both lines have different rtt's tcp will get very confused by constantly arriving out-of-order packets, the performance may be even worse than with just one line. For ethernet bonding may be more appropriate. BTW, the patch was not written by me, i only adapted it to 2.4.18 and fixed some locking bugs. Bye Patrick _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/