Re: [RAM] Number of DFZ routers

Eliot Lear writes:
> Chris L. Morrow wrote:
>> I think that the current 'best' number for this is likely the cisco
>> IDB maximum which is 2048? (idb = interface database) So, at a
>> maximum a router could have 2k interfaces (logical and physical).

>> I suspect that there are DSL platforms that scale beyond this,
>> [...]

> http://www.cisco.com/warp/public/63/idb_limit.html

I think Robin's question was about *operational* routers, i.e.,
configuration of routers in actual use in the Internet, not about
hardware/software limits:

>>> Can anyone  suggest the range of number of interfaces these
>>> routers have?  For  instance, what is the largest number of
>>> interfaces on an operational  router?

We're not a Tier-1, just a backbone for the academic community in a
small country (Switzerland), but since nobody so far gave *any*
numbers from an operational network, here are a few from our network.
Let's hope that this encourages others.

We have 40 backbone/peering/customer access routers.  I'm counting all
non-lab routers running (i)BGP in our backbone AS.

The number of non-tunnel, non-loopback, non-shutdown interfaces on
these routers varies between 3 and 38.  Most of the interfaces are to
point-to-point GigE and 10GE links (and three residual POS links),
with a few to multipoint GigEs (Internet exchange points or customer
DMZ's).  This is an ordered list of #s of non-trivial interfaces for
all our backbone routers:

3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 5 5 5 5 5 5 6 6 6 6 6 7 7 7 9 10 10 15
16 16 17 18 19 23 38

Our network is probably atypical in many respects - we have quite a
few routers with just three interfaces, which is sort-of the minimum
configuration where a router can make any sense at all.  We also have
no lower-speed access links (a single Fast Ethernet, all the rest are
GigE and 10GE).  We also don't run full BGP for IPv4 - 35'000 routes
is sufficient for us, thank you.
-- 
Simon.
SWITCH (AS559)

The following script may help produce numbers if you have Cisco
(-like) routers and use something RANCID:

Re: [RAM] Number of DFZ routers

Attachment: router-stats