policy routing and netflow (was Re: karl and paul, expostulating )
Brett D. Watson
bwatson at genuity.net
Thu Feb 20 22:37:05 UTC 1997
> On Feb 20, 1997, Brett D. Watson wrote:
> > doesn't matter. in production ios, policy routing (source based
> > routing) is process switched. there is code in the works to make it
> > fast switched. but there is a bug wherein if you do policy routing,
> > and you enable flow or optimum switching on the interface you're
> > doing pr on , it disables the policy routing.
> > that bug may be fixed now but in any case enabling flow switching
> > will *not* speed up policy routing. and if you're exporting the flow
> > stats, you lose anywhere from 50kpps to 100Kpps of speed.
> I have news for you; this isn't policy routing!
you better tell cisoc that then :) they call source based routing
"policy routing". bad choice of names i guess but that's what they
call it. it's an inbound route map applied to an interface and you
look at the *source* address of the packet, then use various "set"
clauses based on that address.
> We aren't re-writting
> any source or destination addresses (which is what policy routing
i have news for you, policy routing has nothing to do with
re-writing source or destination addresses.
> We're just filtering based on source and destination
> parameters (such as address, protocol, port, etc).
if you're filtering based on source-anything, and you're using a
cisco, i'd like to know how you're doing it without policy
route-maps. please see:
i didn't imply that you were doing anything. i may have
misundestood justin but i thought he was implying that netflow
switching would increase the switching speed of policy based routing,
as cisco calls it, and it does not. that's all i was getting at.
> Flow switching works very effectively (at least as of IOS 11.1.9).
yes it does. i never said it didn't work well. who's mail were
you reading anyway?
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