Re: [c-nsp] ACL to block udp/0?

2023-12-06 Thread Dobbins, Roland via cisco-nsp
On Dec 6, 2023, at 17:46, Gert Doering wrote: I'd argue that the DNS folks recommend using EDNS0 with 1232 bytes, which works just fine to avoid fragments... Of course, the last true Internet flag day was in 1994, flag days aren’t possible anymore, & this is far from universally implemented.

Re: [c-nsp] ACL to block udp/0?

2023-12-06 Thread Dobbins, Roland via cisco-nsp
On Dec 6, 2023, at 04:45, Gert Doering via cisco-nsp wrote: deny ipv4 any any fragments This is approach is generally contraindicated, as it tends to break EDNS0, & DNSSEC along with it. If the target is a broadband access network, you can use flow telemetry to measure normal rates of

Re: [c-nsp] Netflow vs SNMP

2023-10-02 Thread Dobbins, Roland via cisco-nsp
On 2 Oct 2023, at 17:10, Hank Nussbacher mailto:h...@interall.co.il>> wrote: cache timeout inactive 15 Kentik recommends 15s: This is an old, out-of-date recommendation from Cisco should be retired. 5s is plenty of time for inactive flows. ___

Re: [c-nsp] Netflow vs SNMP

2023-10-02 Thread Dobbins, Roland via cisco-nsp
On 2 Oct 2023, at 13:13, Hank Nussbacher via cisco-nsp mailto:cisco-nsp@puck.nether.net>> wrote: Does this make sense to go 1:1 which will only increase the number of Netflow record to export? Everyone that does 1:1000 or 1:1 sampling, do you also seen a discrepancy between Netflow