Route table growth and hardware limits...talk to the filter

Yes, I would agree this statement is true but some of the tradeoffs seem pretty high.

My statement about routing platforms was more based on the fact that what my Cisco rep said was true - the sup upgrade was gonna be cheaper than 7304s or "option J". I mean yeah, I could buy 7206s but it still wouldn't save me that much.

What just chaps my hide is that there is no reason, in this application, to need 40GB/slot performance. Their refusal to sell a cheaper card with improved TCAM suggests that the SUP720/RSP720 has really high margins and they're making a killing on this issue...

I think one of the points here is that we've gotten beyond the space where two uplinks was "good enough" for virtually all cases and that either uplink was "good enough" provided it is up. And "up" was a binary state rather than an array of binary states with associated keys defined by destinations.

More explicitly, I think those using MSFC2s to take full routes are largely saying "hey, we know what we are doing and why." and "Cisco should have redesigned their boards to support more routes earlier"-- so items like the SUP32 would have a 3BXL option and the like.

From the folks on here who are saying using a default or aggressive route filtering isn't sufficient are also implying they have more than 2 views of the Internet... in many cases many more than 2 transit views, and possibly peers as well.

Certain snobbery aside ("Anyone who needs a M7i doesn't need a full routing table") seems uncalled for. I am not going to comment on J's line up, but a M7i should be able to route 3-4Gb/s to a full table without sweating too hard over a handful of interfaces. How many people are routing 3-4 Gb/s to the Internet and don't have at least several uplinks and LOTS of customers that would get *exceptionally* pissed off at less than ideal routing or routing holes (in this case defined as a default to a provider that has a hole)?

The Cisco 6500/7600 line is amazingly stable and supports a ridiculously high number of 1GE ethernet and 10GE ethernet L3 ports mated to a Cisco<tm> BGP talker. Yes, in the majority, the ports have small interface buffers. Therefore, these are best suited at interfaces between other networks over low-latency intra-building or metro-area cross-connects rather than large-latency international circuits. I suspect that is where the majority are being operated.

If you need a router to talk to your >40ms interfaces, its not for you. If you like to mix and match a lot of media in your router, its not for you. If you have gotten rid of most of that SONET-speed craziness (OC3, OC12, OC48) in your core --even if that just means upgrading to Nx10GE everywhere, and everything has started looking like ethernet, they are exceptionally tasty.

As an operator of such a successful series of equipment that has had a surprisingly long set of legs, I think I would be more impressed if Cisco had a board that had dramatically greater routing capabilities (not just speed, but table size) than the 3BXL. Or if Cisco demonstrated that it understands where these boxes are being used and they all aren't deployed in super-high-density PoE applications or on high-latency overseas interfaces.

But that is neither here nor there. The idea of how to filter has been brought up, in fact, someone posted an actively worked-on filter for US-centric providers that provide some immediate relief. The idea of a code improvement that gives MSFC2s a more graceful fail pattern has been brought up by Lincoln c/o Cisco.

So far, nobody has spoken of a Cisco plan to provide a SUP32-3BXL or similar board for immediate relief of the problem -- so either the NDA has no leaks or its not going to happen in the next few months of operational planning.

Speculation about the alternative platforms (from C or J) is fair game. I suspect J is trying to upsell lots of people from 6500s and 7600s and is realizing that lots of 6500/7600 users don't see the point of paying $7,000 per GigE interface no matter how many bells and whistles one can turn on at the same time. C isn't worried about many defections, nor should it be -- no one has a competing box with the same kind of reputation for ethernet density/stability at the price point. I suspect whoever owns the product line at C is going to get a big bonus this year while he/she struggles to justify why they need to keep increasing the routing capabilities beyond the Sup720-3BXL, at least for the 6500.

This is longer than I had intended. Hopefully something in it is operational.

Deepak Jain
AiNET

Our perceptions differ -- you seem to think that the having full, unfiltered BGP feed protects from these problems. That's not the case. E.g., in the TeliaSonera routing problem I sent on the m-l on Sep 6, all prefixes were received fine through TSIC, but certain traffic ended up being dropped for the duration of about 9 hours.

Unless you made an administrative action on the router, some networks would have been blackholed for 9 hours regardless of the fact whether you used unfiltered BGP or filtered BGP.

So, if you're uncomfortable with such major networks causing problems in your connectivity, you'll need the ops staff to look after the routing and change it if need be. Ergo, if you need the ops staff, you could just as easily as shutdown or depref of a badly behaving transit switch the default or change the other priorities.

I guess the main point here is how prevalent "no reachability, no prefix" scenario is compared to "routing/forwarding broken, manual action required". My take is that the the former is rare with good upstreams and while the latter might not be as frequent as the former, you'll need to prepare for it in any case so the difference likely doesn't matter that much.

Has everyone forgotten the "Tier 1 depeerings" of several years ago? i.e. If you were pointing default at C&W, PSINet, Cogent, or Level3 when they each had or caused depeering issues, parts of the internet ceased to be reachable. In such cases, having full routes from multiple providers was the only way to be automatically protected from such games.

[snip]

Has everyone forgotten the "Tier 1 depeerings" of several years ago? i.e.
If you were pointing default at C&W, PSINet, Cogent, or Level3 when they
each had or caused depeering issues, parts of the internet ceased to be
reachable. In such cases, having full routes from multiple providers was
the only way to be automatically protected from such games.

The triumph of marketing in the so-called tier-1s is just sad.
The continued success of them reflects the lack of... oh wait,
didn't 3561 change hands a lot? And didn't supposedly inferior
edge networks pick up 701, 7018, 174 ....

Perhaps having marketing dictate a fragile network strategy
isn't in the best business interest after all.

My statement about routing platforms was more based on the fact that what
my Cisco rep said was true - the sup upgrade was gonna be cheaper than
7304s or "option J". I mean yeah, I could buy 7206s but it still wouldn't
save me that much.

What just chaps my hide is that there is no reason, in this application,
to need 40GB/slot performance. Their refusal to sell a cheaper card with
improved TCAM suggests that the SUP720/RSP720 has really high margins and
they're making a killing on this issue...

Actually, originally Cisco planned to release SUP32-XL or similar variant
with higher FIB TCAM space. But they scrapped that plan near the end,
screwing many people in the process (I'm sure some cisco account reps got
earful about this from many people who bought sup32's in the past)-- I mean
hey, forcing customers to buy SUP720 plus may be new line cards (depending
on situation) is more revenue right? This whole 220k+ ipv4 routing issue is
an excellent opportunity :slight_smile:

On the other hand, if you have the guts, try popping in a PFC3BXL card into
SUP32. I wonder which IOS versions will actually recognize this and show ~1
mil. entry capacity when doing 'sh mls cef max' :wink: (WARNING: this
completely violates warranty and irreparable damage may occur)

james

James,
So it is the vendor's fault that you didn't properly engineer your
network and size the right kit for the job? Learn a little
engineering 101 to avoid these situations.

James,
So it is the vendor's fault that you didn't properly engineer your
network and size the right kit for the job? Learn a little
engineering 101 to avoid these situations.

Did I ever mention that *I* didn't properly engineer my network (there are
no sup32's on my network as of date)?

Consider your own arrogance before you make idiotic statements that add no
value to discussion.

james

Has everyone forgotten the "Tier 1 depeerings" of several
years ago? i.e.
If you were pointing default at C&W, PSINet, Cogent, or
Level3 when they each had or caused depeering issues, parts
of the internet ceased to be reachable. In such cases,
having full routes from multiple providers was the only way
to be automatically protected from such games.

Not so. Anyone who had sufficient transit was also protected from
the games. Lots of so-called regionals and tier-2 networks were
shielded from this monkey-business. And, of course, they shielded
their customers as well. A tier-1 network operator who operates such
a fragile network becomes a single point of failure. And not just
because of peering as the AT&T frame relay collapse shows.

--Michael Dillon

Michael, how are these two statements not in agreement? It looks to me
like you're saying the same thing: A network which claims "tier 1" status
by failing to buy any transit, subjects its customers to connectivity
failures when depeering happens, while a normal multi-homed network does
not inflict that failure upon its customers. Isn't that what you're both
saying?

Disclaimer: this is my first posting of the morning, thus it's inevitably
dunderheaded or offensive, for which everyone has my apologies in advance.

                                -Bill

I think you've completely missed what I said. If you were pointing default at C&W (whether they were your only connection, or you were "multihomed" but couldn't handle full routes, so perhaps you had customer routes from each provider and default pointing at C&W) when they depeered PSI, single homed (or similarly configured non-full routes) customers of PSI ceased to be reachable. A long time customer of mine was hit by this (their business required communications with one or more single homed PSI customers, and C&W was their sole transit). It was the driving force behind their multihoming. Ever since, they've maintained 3 or more transit providers and full routes from each.

side note: i would not advise relying heavily (e.g pointing default) on
a network which flap damps or relies on upstreams which damp. one
teensie weensie flappipoo and you could be dead meat.

randy

    > > having full routes from multiple providers was the only way
    > > to be automatically protected.
    >
    > Not so. Anyone who had sufficient transit was also
protected from
    > the games. And they shielded their customers as well.

Michael, how are these two statements not in agreement? It
looks to me like you're saying the same thing: A network
which claims "tier 1" status by failing to buy any transit,
subjects its customers to connectivity failures when
depeering happens, while a normal multi-homed network does
not inflict that failure upon its customers. Isn't that what
you're both saying?

I suppose that if you dig deeper, which most people don't seem to do,
then buying transit is just one form of having full routes from
multiple providers. But on the surface, the comment that I responded
to seemed to be repeating that commonly held belief than only
transit-free, default-free providers with multiple peers for
any given prefix, can be considered Tier 1. Last century, there
was lots of boasting in the business and people needed rules of
thumb such as "default free" and "transit free" to sift the wheat
from the chaff. But I don't think that is true anymore, especially
not on a global scale (even a partly global scale). There are providers
who provide high levels of service and reliability who have some
transit and some default routes in the mix.

I'd like to see a lot more focus on how a network deals with single
points of failure, physical separacy of links, and the like. These
are more important than whether they are a pure-play peering network.

Disclaimer: this is my first posting of the morning, thus
it's inevitably dunderheaded or offensive, for which everyone
has my apologies in advance.

Not at all. It is inevitable to have misunderstandings when going
through
a paradigm change. We went through the last one when the telecom
industry
bought up the ISP industry. But now we are going through another one as
businesses higher up the OSI stack, like Google, are getting into
running
an IP WAN. Also, traditional telecom companies are diversifying into
other service areas higher up the stack in a similar way to how IBM
branched
out from being a computer hardware manufacturer into a services company.

--Michael Dillon

Well, taken in its entirety, that's the null set. Hypothetically, setting
aside the issue of mainland China, it could be the case that there would
be a set of providers which were transit-free. However, if they were
transit-free, they would, by definition, never have more than one peer for
any single-homed prefix.

But in any event, pretty much the definition of "tier 1" is the subset of
providers which claim not to buy transit, and peer with each other, and
not with anyone else.

Whether or not that set is empty or populated is one issue.
  
Whether the term is a useful one is a different issue.

How much of a liability it would be to one's self and one's customers to
find one's self in that set is a third issue.

But I'm not convinced we have a disagreement on our hands here. Just more
of an argument. :slight_smile:

                                -Bill

However, if they were transit-free,
they would, by definition, never have more than one peer for
any single-homed prefix.

And that sounds like a single point of failure to me. Let's look
at it another way by considering the path to any prefix. If there
is only one single path available, and a single event, such as the
depeering by one ASN, can lead to that path being broken, then you
have a network whose connectivity is not terribly robust.

If a network bites the bullet, and either openly buys transit, or
works out some partnership peering plus transit deal to hide the fact
that they have transit, then there is the possibility of having
two paths for every prefix. If they then take the trouble to analyze
the paths and adjust things to make sure that the multiple paths
to a single prefix don't share fate, then they stand a good chance
of having a robust network.

The thinking, and the work involved, are a lot like what you need
to do in order to ensure physical separacy of fibre paths. It's the
same fundamental problem but perhaps more dynamic since circuits tend
to get groomed less often than paths change.

--Michael Dillon

Hello,

Can a Yahoo! Mail/SysAdmin contact me off list? I am having a problem
with multiple mail servers within our network not being able to send to
Yahoo mail servers.

Thanks,

Raymond Corbin
Support Analyst
HostMySite.com

http://help.yahoo.com/l/us/yahoo/mail/yahoomail/postmaster/

I've used those forms. All I get are canned responses :confused:

-Ray

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I've used those forms. All I get are canned responses :confused:

Such is the art of sending email these days...

- --
Ken Simpson
CEO, MailChannels

Fax: +1 604 677 6320
Web: http://mailchannels.com
MailChannels - Reliable Email Delivery (tm)

Hi Ray,

And Yahoo's better than MSN at having a live body resolve the issue...
Good luck. Hopefully, someone at Yahoo! Has heard you. :slight_smile:

-J