[184399] in North American Network Operators' Group
Re: /27 the new /24
daemon@ATHENA.MIT.EDU (Mel Beckman)
Fri Oct 2 15:22:35 2015
X-Original-To: nanog@nanog.org
From: Mel Beckman <mel@beckman.org>
To: Mike Hammett <nanog@ics-il.net>
Date: Fri, 2 Oct 2015 19:22:29 +0000
In-Reply-To: <8965468.2594.1443811120487.JavaMail.mhammett@ThunderFuck>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
Often I find that used Cisco gear is more reliable and just as affordable t=
han newer gear with that tasty, flakey crust. I've had a terrible time with=
CCRs falling over with 1GB traffic while Cisco L3 3750s don't even breathe=
hard at 10Gbps. I see no reason to use anything like 2500w even with Cisco=
gear. A dual Cisco 3750 stack consumes maybe 500W. Cisco firmware, for all=
its faults, seems to be much better tested than Mikrotik's.=20
I once asked Mikrotik's support engineers how they performed regression tes=
ting, and they said "because we are a small, agile, disruptive innovator we=
don't follow old-school testing regimens. We're more interested in shippin=
g affordable product." That's also their excuse for poor documentation.=20
From what I can see, "small, agile, disruptive innovator" is an excuse newe=
r networking companies often give for "sloppy, poorly tested, ill-conceived=
" product development.=20
-mel beckman
> On Oct 2, 2015, at 11:44 AM, Mike Hammett <nanog@ics-il.net> wrote:
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> Chances are the revenue passing scales to some degree as well. Small busi=
ness with small bandwidth needs buys small and has small revenue. Big busin=
ess with big bandwidth needs buys big and has big revenue to support big ro=
uter.=20
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> I can think of no reason why ten years goes by and you haven't had a need=
to throw out the old network for new. If your business hasn't scaled with =
the times, then you need to get rid of your Cat 6500 and get something more=
power, space, heat, etc. efficient.=20
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> I saw someone replace a stack of Mikrotik CCRs with a pair of old Cisco r=
outers. I don't know what they were at the moment, but they had GBICs, so t=
hey weren't exactly new. Each router had two 2500w power supplies. They'll =
be worse in every way (other than *possibly* BGP convergence). The old setu=
p consumed at most 300 watts. The new setup requires $500/month in power...=
and is worse.=20
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> Stop using old shit.=20
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> -----=20
> Mike Hammett=20
> Intelligent Computing Solutions=20
> http://www.ics-il.com=20
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> Midwest Internet Exchange=20
> http://www.midwest-ix.com=20
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> ----- Original Message -----
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> From: "William Herrin" <bill@herrin.us>=20
> To: "Mike Hammett" <nanog@ics-il.net>=20
> Cc: "NANOG" <nanog@nanog.org>=20
> Sent: Friday, October 2, 2015 1:09:16 PM=20
> Subject: Re: /27 the new /24=20
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>> On Fri, Oct 2, 2015 at 11:50 AM, Mike Hammett <nanog@ics-il.net> wrote:=
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>> How many routers out there have this limitation? A $100 router=20
>> I bought ten years ago could manage many full tables. If=20
>> someone's network can't match that today, should I really have=20
>> any pity for them?
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> Hi Mike,=20
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> The technology doesn't work the way you think it does. Or more=20
> precisely, it only works the way you think it does on small (cheap)=20
> end-user routers. Those routers do everything in software on a=20
> general-purpose CPU using radix tries for the forwarding table (FIB).=20
> They don't have to (and can't) handle both high data rates and large=20
> routing tables at the same time.=20
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> For a better understanding how the big iron works, check out=20
> https://www.pagiamtzis.com/cam/camintro/ . You'll occasionally see=20
> folks here talk about TCAM. This stands for Ternary Content=20
> Addressable Memory. It's a special circuit, different from DRAM and=20
> SRAM, used by most (but not all) big iron routers. The TCAM permits an=20
> O(1) route lookup instead of an O(log n) lookup. The architectural=20
> differences which balloon from there move the router cost from your=20
> $100 router into the hundreds of thousands of dollars.=20
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> Your BGP advertisement doesn't just have to be carried on your $100=20
> router. It also has to be carried on the half-million-dollar routers.=20
> That makes it expensive.=20
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> Though out of date, this paper should help you better understand the=20
> systemic cost of a BGP route advertisement:=20
> http://bill.herrin.us/network/bgpcost.html=20
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> Regards,=20
> Bill Herrin=20
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> --=20
> William Herrin ................ herrin@dirtside.com bill@herrin.us=20
> Owner, Dirtside Systems ......... Web: <http://www.dirtside.com/>=20
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