nanog mailing list archives
Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?]
From: Seth Mattinen <sethm () rollernet us>
Date: Wed, 05 Feb 2014 16:34:59 -0800
On 2/5/14, 13:24, Jay Ashworth wrote:
The common answer, Octavio, at least*used to* be "our line cards aren't smart enough to implement strict-unicast-RPF, and our boxes don't have enough horsepower to handle every packet through the CPU". As I've noted, I'm not sure I believe that's true of current generation gear, and if it*is*, then it should cost manufacturers business.
In Cisco 6500 land - which were very popular - Earl7 uRPF is limited to one of strict or loose (no mixing modes) for IPv4 only. Otherwise you have to rely on ACLs and the possibility of running out of TCAM space for them depending on density.
The Sup2T (Earl8) does fix these limitations: uRPF is configurable per-interface basis and independent of IPv4/IPv6, and can be a mix of loose or strict mode. But Sup2T only came out in 2011.
~Seth
Current thread:
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?], (continued)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Livingood, Jason (Feb 04)
- RE: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Frank Bulk (Feb 04)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Livingood, Jason (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Christopher Morrow (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Robert Drake (Feb 06)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Jay Ashworth (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] joel jaeggli (Feb 05)
- BCP38 is hard; let's go shopping! Jay Ashworth (Feb 05)
- Re: BCP38 is hard; let's go shopping! joel jaeggli (Feb 05)
- Re: BCP38 is hard; let's go shopping! Christopher Morrow (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Seth Mattinen (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Mark Tinka (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Jay Ashworth (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Mark Tinka (Feb 05)
- Re: BCP38 [Was: Re: TWC (AS11351) blocking all NTP?] Jay Ashworth (Feb 05)
- Re: TWC (AS11351) blocking all NTP? William Herrin (Feb 04)
- Re: TWC (AS11351) blocking all NTP? Jared Mauch (Feb 04)
- Re: TWC (AS11351) blocking all NTP? Jay Ashworth (Feb 04)
- Re: TWC (AS11351) blocking all NTP? Michael Smith (Feb 06)
- Re: TWC (AS11351) blocking all NTP? Doug Barton (Feb 04)
- Re: TWC (AS11351) blocking all NTP? William Herrin (Feb 04)