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Re: [LUG] Data centre in Cornwall

 

Simon Avery wrote:
> 
> That said, I'm sure there's a very big market for people who are very 
> happy with 99% uptime

Come have a web server that is down 3.5 days a year isn't a good sales 
pitch.

But I think you can achieve better than 99% relatively easily, without 
massive investment.

Working somewhere that offers colo in Exeter as a side line in a very 
small way, I'd prefer to be in a bigger computing facilities with better 
aircon, and better power. Economies of scale are critical here.

On our main web server....

  uptime
  12:29:54 up 521 days, 17:20,  2 users,  load average: 1.19, 0.73, 0.58

The long overdue upgrade to Etch will stop that.

Probably a bigger issue is that whilst 521 days looks good this is 
uptime, just reflects when we last lost power to that rack. Service 
availability hasn't been 100% for 521 days (I wish). Not least I've 
rebooted the traffic shaper a couple of times to keep it patched and in 
a supported release. So even a straight web server has a switch, a 
traffic shaper, and a router in front of it, all of which can contribute 
to downtime (on top of loss of power, or aircon, or network connectivity].

So the reason for apparent over specification of hosting facilities is 
that downtime doesn't add up nicely, and big customers will want more 
than 99% expected uptime (since like us they'll have quite enough 
planned downtime for things like upgrades).

A lot of course goes into what happens when you don't achieve the SLA.

Our customers understand it is a best effort, and we don't have penalty 
clauses for failing to achieve a given availability. If we did, we'd 
have to charge a lot more, and we'd have a lot more redundancy to make 
sure we never give them any money back.

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