RE: availability and resiliency

[Leo Nelson <lnelson () axient com>]

Thank all of you who responded. I appreciate it.
 
-leo

-----Original Message-----
From: Chris Flores [mailto:chris.flores () onfiber com]
Sent: Friday, September 29, 2000 10:20 AM
To: 'Leo Nelson'; 'nop () alt net'; Andrew Bangs
Cc: nanog () merit edu
Subject: RE: availability and resiliency


Leo - 
 
The '9' refers to a specific SLA (service level agreement). 5 9's is the
guaranteed amount of network uptime. Another way to state 5 9's is - 99.999%
uptime. This of course yields the amount of time a customer's service is not
available. 5 9's is equivalent to 315 un-available seconds per year or 5
minutes.
 
Best regards.
 
Chris

-----Original Message-----
From: Leo Nelson [mailto:lnelson () axient com]
Sent: Friday, September 29, 2000 12:08 PM
To: 'nop () alt net'; Andrew Bangs
Cc: nanog () merit edu
Subject: RE: availability and resiliency



Pardon my ignorance, but what the heck does a "9" refer too? Is it a UPS,
rack, floor space, circuit... 

Thanks in advance 
-leo 

-----Original Message----- 
From: Lionel Lauer [ mailto:longword () newsguy com
<mailto:longword () newsguy com> ] 
Sent: Friday, September 29, 2000 10:54 AM 
To: Andrew Bangs 
Cc: nanog () merit edu 
Subject: Re: availability and resiliency 



On Fri, 29 Sep 2000 17:39:04 +0100, Andrew Bangs <andrewb () demon net> 
wrote: 

> On Thu, Sep 28, 2000 at 02:39:40PM -0600, Irwin Lazar wrote: 
> > Hi all, 
> > Does anyone know if a template exists for what it takes to provide 5 9's
of 
> > availability, 4 9's etc.for Internet data centers?  Specifically I'm
looking 
> > for something that would say "if you want 5 9's of availability, here's
what 
> > you need to do", and so on. 
>
> For 5 9s you need: 
>
> 1) Lots of money 
> 2) Lots of clue 
> 3) Lots of luck 
> 4) Lots of balls 
>
> You can do 4 9s with any 3 of the above. 

Too true. 

But you forgot to include 'halfway-clued management' - without that you 
haven't got a hope in hell of even getting three 9's. ;) 

-- 
   W          
 . | ,. w ,   "Some people are alive only because 
  \|/  \|/     it is illegal to kill them."    Perna condita delenda est 
---^----^---------------------------------------------------------------