[quagga-users 14368] Re: How to limit Quagga Buffers

Richard Mayers richard.mayers92 at gmail.com
Fri Jul 22 19:12:25 BST 2016

Hi again,

As you said I had to modify some of the kernel buffers, rmem_default,
wmem_default , rmem_max, wmem_max.

However, if I put them quite small, the routers start doing strange
things. For example they start reporting 0% link usage when I am
sending traffic, everything quite random...

Does anyone know what could be the reason ? What could go wrong when
the buffers are small ? Apart from packet loss.

Kind regards,

2016-07-21 23:03 GMT+02:00 Richard Mayers <richard.mayers92 at gmail.com>:
> Hi,
> Thanks, that has sense. I am using linux, so I guess I have to find
> which buffers do that and change the size value of those kernel
> buffers.
> Kind regards,
> Richard
> 2016-07-21 21:51 GMT+02:00 Lennart Sorensen <lsorense at csclub.uwaterloo.ca>:
>> On Thu, Jul 21, 2016 at 09:40:18PM +0200, Richard Mayers wrote:
>>> Hi folks,
>>> I have the feeling that my quagga routers have infinite buffers and I
>>> never experience losses when sending UDP traffic.
>>> For example:
>>> Lets say I have a router with two links     ------(20mbps)------
>>> Router -----(10mbps)------ If I send traffic to the router through the
>>> first interface at 20mbps it sends 10mbps because its the maximum it
>>> can do, however it buffers the rest and when I stop sending traffic
>>> the router will keep sending through the second interface.
>>> I do not want this to happen I want the packets to be lost. What
>>> should to have small buffers?
>> Quagga does NOT route packets.  That is your OSs job.
>> quagga just moves information about what routes exist around.
>> So depending on which OS you are running you would need to figure out
>> how to configure it.
>> --
>> Len Sorensen

More information about the Quagga-users mailing list