[c-nsp] sup720 ICMP redirects "once per second"

[Jared Mauch]

On Feb 11, 2013, at 9:17 AM, Phil Mayers <p.mayers at imperial.ac.uk> wrote:

> All,
> 
> Does anyone know which knob controls the "only send 1 ICMP redirect / sec" on an HSRP-enabled SVI on 6500/sup720 (SXJ IOS)? Is there a "show" command for the defaults / current setting?
> 
> Note: I am not talking about the redirect MLS rate-limiter here; that's disabled. I'm seeing constant traffic flowing and would expect constant ICMP redirects, but that's not happening - they're coming at regular 1-second intervals, regardless of the underlying packet arrival rate.

This may be some limiter similar to that which first showed up in Solaris 2.6 for the icmp error rate.

I know that we always turn off IPv4 and IPv6 redirects to avoid even generating them.  It's typically best used with the "ip route-ca same-interface" command.

If folks want to hairpin traffic, that's fine.. just want to prevent slowing it down.

- Jared