David Barak wrote:
the m7i is a lot of power for not so much money,
If you know of one for sale for 5K, please let me know.
Rodney Dunn wrote:
That's the most common deployment mistake I see made
with the 75xx nowadays. People want to move to dCEF to
get added feature capability or either run a new feature
that requires dCEF and they don't consider the extra
load on the VIP CPU's that is required.
Does dCEF use much more CPU on the VIPs or just memory
(to store the fowarwarding table on the VIP)?
Oh yes. And there are plenty of ways to mess it up, too. I never dared
running things such as QoS policy propagation via BGP plus dCAR/dwRED on
a 7500. Maybe on a VIP6, any takers? On a VIP2-50/128 as Alexander
mentioned, fugged about any extra features.
My experience has been that a 7500 with RSP4's and VIP2-50's
(with dCEF) will handle much more packet forwarding than a
This is true but only if you're not fancy. VIP2-50 is a 200Mhz R5000,
that's slightly better than a 3640, not fast by any means. That's what
you find in a PDA these days. Just handling traffic for two FE PAs will
get it pretty busy already.
but with full BGP routes, you need at least 64mb (preferably
128mb) on the VIPs or you can't use dCEF. Not using dCEF
largely defeats the purpose of using a 7500, doesn't it?
You'd get a 7507 (only if it were a choice between that
or a 7505?), but then at the end of your message, you say
you wouldn't buy any 7500?
Only if it were a choice between that and a 7505.
A basic 7507 (dual PS, dual RSP4, couple of VIPs and PAs)
is so cheap today, if he's strapped for cash, that's what
I'd go for. I'm guessing you can still get at least several
years out of such a box, and by the time you've outgrown it
or cisco stops making IOS for it (they still make IOS for
AS5200's!), hopefully you'll have the cashflow to upgrade.
That summarizes is well, it's a pay me now or pay me later thing. The
7206 might be a little pricier but it will last longer, and that's one
thing to take into account when capexing hardware. The bottom line is
that as of today and given 400Mbps of traffic it does cost big buck$ to
upgrade the 7500 to RSP16 and VIP6 to be able to run everything, and
that would not be a wise investment I think.