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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Load balancing in routers
a large router running low bandwidth will be fine but as was previously said, if you do this on most properly sized routers you will use all the cpu another thing is you will see increased latency and jitter as your packets individually queue for cpu process time Steve On Mon, 8 Apr 2002, Mark Kent wrote: > > >> > load balancing over multiple links uses a flow-hashed method. If you > >> > want per-packet load distribution you have to specifically enable it by > >> > saying "no ip route-cache" on each interface. > >> > >> That is very deadly, please, don't anyone actually try that. > > How so? So it uses a little more cpu, but that may not be relevant in > a lot of applications (like down at the T1 level). > > I've had a customer on the end of 8 T1, no ip route cache, on a 4700 > (their end) and a 7206/300 (my end). 4700 runs a little hot, but survives. > > Similarly, I currently have a couple of 4*T1, a 3*T1, and several 2*T1 > on PA-MC-T3 ports on a 7206/300 with no issues whatsoever. Max cpu > usage is 35%. Everything works. > > Now, contrast that with my first use of cef, this was back when the > only cef configuration was "ip cef" or something similar. Very > difficult to screw things up when the config is a one-liner, and yet > when I turned this on the 7206 immediately crashed. > > -mark > > -- Stephen J. Wilcox IP Services Manager, Opal Telecom http://www.opaltelecom.co.uk/ Tel: 0161 222 2000 Fax: 0161 222 2008
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