Route table growth and hardware to the filter

John A. Kilpatrick john at
Fri Sep 21 08:52:19 UTC 2007

On 9/20/07 4:40 PM, "Jon Lewis" <jlewis at> wrote:

> No, but someone previously posted that with later software versions, when
> TCAM runs out, packets for those routes that fit in TCAM are hardware
> switched, and only traffic for the remaining routes that didn't fit are
> software switched.

That is what I thought as well, but I'm afraid the only MSFC2s I have are
attached to my SUP32s in production.  And so destructive testing like this
would be, you know, bad.  But it would be really good to know what to
expect. One possibility means that we might see occasional CPU spikes.  The
other possibility means the box will start sucking more than this year's
factory Honda team.  I suppose I could ask Cisco, but if anyone else has
done any testing it'd be good to hear about it...

Meanwhile, I have brought myself to three options:

1.  Upgrade to RSP720-3CXL (same price, more memory, faster CPU compared to
SUP720-3BXL) + 6148s
2.  Cisco 7304 + pair of 3750s
3.  Juniper M7i + pair of 3750.

Even with need for the 6148s it's still cheaper for me to keep my 7604s
although not by too much. Now to get in to the nitty gritty.  Imagine my
shock when my Cisco rep said he's been having a lot of these conversations

                                John A. Kilpatrick
john at                Email|
john-page at      Text pages|          ICQ: 19147504
                  remember:  no obstacles/only challenges

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