Re: UUnet blocking ICMP ECHO for select sources/destinations ?

[Kai Schlichting <kai () pac-rim net>]

The observations suggest something different. Remember that I mentioned
that this blockage only occurs for a SINGLE IP in my network: the base
IP belonging to the server doing the stats collection every 5 minutes. Other
IP's (even on that server) are ok. Rate limiting would be visible as packet
loss after the committed rate is exceeded: you can't rate-limit on production border routers down to single-host 
granularity, only a big interface-wide
rate-limit will work. I am still trying to determine if the interface IP
in question is the customer side of things, but things are a bit murky
there, because there appear to be ACLs on both sides of the link.



At Wednesday 04:15 PM 6/14/00 , Mufti Ahmed <Mufti.Ahmed () reuters com> wrote:


>  Kai what if UUnet  is  running some type of QOS mechanism in their
> core network that prevents massive amounts of icmp messages
> traveling through? Maybe they are rate-limiting everyone with CAR.
> Their infrastructure is interesting they use Cisco, Fore, and Juniper
> at least in production. And they claim they run an MPLS network;
> maybe this is where icmp traffic is killed..