We _always_ have at least one spare, or something that could be (relatively) 
easily pressed into service as one. 
 
Even in the Midwest, we've had times where 'guaranteed next day replacement' is 
more like 2nd or third day due to weather conditions, the carrier routing it 
weird, or just plain the plane didn't come today issues.  We generally laugh 
when they try to offer us 4 hour contracts -- we know there's 0 chance they can 
meet them, and they never want to refund you when you need it and they can't.
 


-----Original Message-----
From: "Warren Kumari" <war...@kumari.net>
Sent: Wednesday, June 17, 2020 6:50pm
To: "Owen DeLong" <o...@delong.com>
Cc: nanog@nanog.org
Subject: Re: Router Suggestions






On Tue, Jun 16, 2020 at 5:28 PM Owen DeLong <[ o...@delong.com ]( 
mailto:o...@delong.com )> wrote:

 > On Jun 16, 2020, at 1:51 PM, Mark Tinka <[ mark.ti...@seacom.mu ]( 
 > mailto:mark.ti...@seacom.mu )> wrote:
 > 
 > 
 > 
 > On 16/Jun/20 22:43, Owen DeLong wrote:
 > 
 >> Covering them all under vendor contract doesn’t necessarily guarantee that
 >> the vendor does, either. In general, if you can cover 10% of your hardware
 >> failing in the same 3-day period, you’re probably not going to do much 
 >> better
 >> with vendor support.
 > 
 > In my experience, our vendors have been able to abide by their
 > obligations when we've had successive failures in a short period of
 > time, as long as our subscription is up-to-date.
 > 
 > I am yet to be disappointed.
 > 

 Count your blessings… I once faced a situation where a vendor had shipped a 
batch of defective power supplies (10s of thousands of them). It wasn’t just my 
network facing successive failures
 in this case, but widespread across their entire customer base… By day 2, all 
of their depots were depleted and day 3 involved mapping out “how non-redundant 
can we make the power in our
 routers to cover the outages that we’re seeing without causing more outages 
than we solve?”

 It was a genuine nightmare.
Huh, was this in the early to mid 1990’s?
I had an incident in NYC area where one of the large (at the time) 
datacenter/IXPs had a power outage, and their transfer switch failed to switch 
over. Customers were annoyed, so they promised another test, which also failed, 
dropping power to the facility again... now customers were hopping mad...
The next test was *just* of the generator, but with all of the work they had 
done they had (somehow) gotten the transfer switch *really* confused / 
hardwired into an odd state. This resulted in the facility being powered by 
both the street power and the generator (at least for a few seconds until the 
generator went “Nope!”)
 These were of course not synchronized, and so 120V equipment saw 0V, then 
240V, then some weird harmonic, then other surprising values. .. most supplies 
kind of dealt with this OK, but one of the really common models of router, from 
the largest vendor upped and died. This resulted in a few hundred dead routers 
and way exceeded the vendors spares strategies.
A number of customers (myself included) had 4 hour replacement contracts, which 
the vendor really could not meet - so we agreed to take a new, much 
larger/better model as a replacement.
W

 I’ve had other situations involving early failures of just released line cards 
and such as well.

 As I said, YMMV, but I’m betting your vendor doesn’t stock a second copy of 
every piece of covered equipment in the local depot. They’re playing the 
statistical probabilities just
 like anyone else stocking their own spares pool. The biggest difference is 
that they’re
 spreading the risk across a (potentially) much wider sample size which may 
better normalize
 the numbers.

 Owen

-- 

I don't think the execution is relevant when it was obviously a bad idea in the 
first place.
This is like putting rabid weasels in your pants, and later expressing regret 
at having chosen those particular rabid weasels and that pair of pants.
   ---maf

Reply via email to