Re: OSPF eequal-cost paths, which algorithm, how exactly load balancing ?

[ Available lists | Index of freebsd-net | Month of May 1999 | Week of 29 May 1999 | Raw email | View thread | Wrap long lines | Reply | Tag ]
From
Andreas Klemm <andreas@klemm.gtn.com>
Date
29 May 1999 04:12:13
Subject
Re: OSPF eequal-cost paths, which algorithm, how exactly load balancing ?
Message-ID
19990529131131.A8802@titan.klemm.gtn.com

References to

[ Hide this part ]
Hi,

thanks for the many people answering.

I learned the following:

a) turning off the fast cache on a Cisco Router with two 2 MBit
serial lines puts too much load on the CPU and isn't suggested.

b) The routing protocol only fills the routing table with
two paths for the destination router / network. How the
packets travel to the dstination network is a matter of
the router operating system (IOS)...

c) If the first packet arrives on the source router (the one
who sits on the backbone from which two equal-cost paths
lead to the destination router) the router doesn't find an
entry in the fast cache and has to look up the routing-table.
When finding a route it makes a "random" decision, which path
to use, transmits the packet and makes an entry in the fast cache.

d) the entry of the fast cache usually has a lifetime of about 10-15
seconds. Subsequent packets will choose the path which is
in the fast cache which, and the fast cache will life for another
10-15 seconds.

e) If no subsequent packets arrive the fast-cache times out.
If a new packet arrives for the destination it starts again
at c)...

So my initial question wasn't correct, assuming the routing protocol
had something to do with the transport through path 1 or 2 ...

I thought I should give you something back, after increasing my
learning courve ;-)

Thanks again

Andreas ///

--
Andreas Klemm http://www.FreeBSD.ORG/~andreas
http://www.freebsd.org/~fsmp/SMP/SMP.html
powered by Symmetric MultiProcessor FreeBSD


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message



Elapsed time: 0.142 seconds