Plethora of UUnet outages and instabilities

Brian Behlendorf wrote:

At 09:49 AM 7/1/97 +0200, Hank Nussbacher forwarded from Network World:
> UUNET started upgrading the memory on the routers, which Cisco
> contends was the real culprit. Cisco recommends that its ISP
> customers use 128M bytes of total memory on their route switch
> processor boards, Michelet said. UUNET uses 64M-byte memory boards
> on most, if not all, of its 7,500 routers.
>
> UUNET said it never received a recommendation from Cisco concerning
> memory for its 7,500 routers. ``But clearly, once this event
> occurred, we discussed the memory issue with Cisco, and we agreed
> the right course of action would be to upgrade the routing memory to
> 128�M bytes�,'' said Jim McManus, vice president of systems
> engineering at UUNET.

Ouch! A couple of questions:

1) Is the "7500" the actual number of routers they'll have to upgrade, or
are they referring to the Cisco 7500 product line? That's an awful lot of
routers to upgrade, so UUnet could have problems for awhile.

2) What could have caused the memory requirements to jump so dramatically?
And if it's due to the routing table "for the whole Internet", why weren't
others affected?

My guess is it was a memory leak of some sort on Cisco's part; NETCOM has
run into a few of these lately. (Thankfully, we caught them before they
got out of hand) There seem to be a few bugs in IOS that cause severe
memory fragmentation; we've gotten fixes for *several* bugs of this type
over the last year, on various platforms. (The latest is one that
fragments I/O memory on 25XX routers; thankfully, this doesn't affect the
core)

+j