nanog mailing list archives
Re: MTU to CDN's
From: William Herrin <bill () herrin us>
Date: Thu, 18 Jan 2018 20:44:20 -0500
On Thu, Jan 18, 2018 at 7:41 PM, Jared Mauch <jared () puck nether net> wrote:
On Jan 18, 2018, at 7:32 PM, William Herrin <bill () herrin us> wrote: On Thu, Jan 18, 2018 at 7:14 PM, Jared Mauch <jared () puck nether net> wrote:lets say i can send you a 9K packet. If you receive that frame, and realize you need to fragment, then it’s your routers job to slice 9000 into 5 x 1500.In practice, no, because the packet you sent had the "don't fragment" bit set.Which packet? Is there a specific CDN that does this? I’d be curious to see data vs speculation.
Howdy, Path MTU discovery (which sets the DF bit on TCP packets) is enabled by default on -every- operating system that's shipped for decades now. If you don't want it, you have to explicitly disable it. Disabling it for any significant quantity of traffic is considered antisocial since routers generally can't fragment in the hardware fast path. Regards, Bill -- William Herrin ................ herrin () dirtside com bill () herrin us Dirtside Systems ......... Web: <http://www.dirtside.com/>
Current thread:
- Re: MTU to CDN's, (continued)
- Re: MTU to CDN's Mikael Abrahamsson (Jan 08)
- Re: MTU to CDN's Vincent Bernat (Jan 09)
- Re: MTU to CDN's Dovid Bender (Jan 18)
- Re: MTU to CDN's George Michaelson (Jan 18)
- Re: MTU to CDN's Mark Andrews (Jan 18)
- Re: MTU to CDN's George Michaelson (Jan 18)
- Re: MTU to CDN's Jared Mauch (Jan 18)
- Re: MTU to CDN's William Herrin (Jan 18)
- Re: MTU to CDN's Owen DeLong (Jan 18)
- Re: MTU to CDN's Jared Mauch (Jan 18)
- Re: MTU to CDN's William Herrin (Jan 18)
- Re: MTU to CDN's Jared Mauch (Jan 19)
- Re: MTU to CDN's Jared Mauch (Jan 19)
- Re: MTU to CDN's William Herrin (Jan 19)
- Re: MTU to CDN's Radu-Adrian Feurdean (Jan 19)
- Re: MTU to CDN's Mark Andrews (Jan 19)
- Re: MTU to CDN's Mikael Abrahamsson (Jan 19)
- Re: MTU to CDN's Vincent Bernat (Jan 18)
- Message not available
- Message not available
- Re: MTU to CDN's Michael Crapse (Jan 18)
- Re: MTU to CDN's Mikael Abrahamsson (Jan 18)
- Re: MTU to CDN's Mike Hammett (Jan 19)